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revision 1.6, Wed May 4 03:24:43 2005 UTC revision 1.75, Thu Nov 9 21:21:49 2006 UTC
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2    
3          use strict;          use strict;
4          use Tracer;          use Tracer;
5          use DBKernel;      use DBrtns;
6          use Data::Dumper;          use Data::Dumper;
7          use XML::Simple;          use XML::Simple;
8          use DBQuery;          use DBQuery;
9          use DBObject;          use DBObject;
10          use Stats;          use Stats;
11          use Time::HiRes qw(gettimeofday);          use Time::HiRes qw(gettimeofday);
12        use Digest::MD5 qw(md5_base64);
13        use FIG;
14        use CGI;
15    
16  =head1 Entity-Relationship Database Package  =head1 Entity-Relationship Database Package
17    
# Line 32  Line 35 
35  relation that contains two fields-- the feature ID (C<id>) and the alias name (C<alias>).  relation that contains two fields-- the feature ID (C<id>) and the alias name (C<alias>).
36  The B<FEATURE> entity also contains an optional virulence number. This is implemented  The B<FEATURE> entity also contains an optional virulence number. This is implemented
37  as a separate relation C<FeatureVirulence> which contains an ID (C<id>) and a virulence number  as a separate relation C<FeatureVirulence> which contains an ID (C<id>) and a virulence number
38  (C<virulence>). If the virulence of a feature I<ABC> is known to be 6, there will be one row in the  (C<virulence>). If the virulence of a feature I<ABC> is known to be 6, there will be one row in
39  C<FeatureVirulence> relation possessing the value I<ABC> as its ID and 6 as its virulence number.  the C<FeatureVirulence> relation possessing the value I<ABC> as its ID and 6 as its virulence
40  If the virulence of I<ABC> is not known, there will not be any rows for it in C<FeatureVirulence>.  number. If the virulence of I<ABC> is not known, there will not be any rows for it in
41    C<FeatureVirulence>.
42    
43  Entities are connected by binary relationships implemented using single relations possessing the  Entities are connected by binary relationships implemented using single relations possessing the
44  same name as the relationship itself and that has an I<arity> of 1-to-1 (C<11>), 1-to-many (C<1M>),  same name as the relationship itself and that has an I<arity> of 1-to-1 (C<11>), 1-to-many (C<1M>),
# Line 56  Line 60 
60  B<start-position>, which indicates where in the contig that the sequence begins. This attribute  B<start-position>, which indicates where in the contig that the sequence begins. This attribute
61  is implemented as the C<start_position> field in the C<IsMadeUpOf> relation.  is implemented as the C<start_position> field in the C<IsMadeUpOf> relation.
62    
63  The database itself is described by an XML file using the F<ERDatabase.xsd> schema. In addition to  The database itself is described by an XML file. In addition to all the data required to define
64  all the data required to define the entities, relationships, and attributes, the schema provides  the entities, relationships, and attributes, the schema provides space for notes describing
65  space for notes describing the data and what it means. These notes are used by L</ShowMetaData>  the data and what it means. These notes are used by L</ShowMetaData> to generate documentation
66  to generate documentation for the database.  for the database.
67    
68    Special support is provided for text searching. An entity field can be marked as <em>searchable</em>,
69    in which case it will be used to generate a text search index in which the user searches for words
70    in the field instead of a particular field value.
71    
72  Finally, every entity and relationship object has a flag indicating if it is new or old. The object  Finally, every entity and relationship object has a flag indicating if it is new or old. The object
73  is considered I<old> if it was loaded by the L</LoadTables> method. It is considered I<new> if it  is considered I<old> if it was loaded by the L</LoadTables> method. It is considered I<new> if it
74  was inserted by the L</InsertObject> method.  was inserted by the L</InsertObject> method.
75    
76  To facilitate testing, the ERDB module supports automatic generation of test data. This process  =head2 XML Database Description
77  is described in the L</GenerateEntity> and L</GenerateConnection> methods, though it is not yet  
78  fully implemented.  =head3 Data Types
79    
80    The ERDB system supports the following data types. Note that there are numerous string
81    types depending on the maximum length. Some database packages limit the total number of
82    characters you have in an index key; to insure the database works in all environments,
83    the type of string should be the shortest one possible that supports all the known values.
84    
85    =over 4
86    
87    =item char
88    
89    single ASCII character
90    
91    =item int
92    
93    32-bit signed integer
94    
95    =item counter
96    
97    32-bit unsigned integer
98    
99    =item date
100    
101    64-bit unsigned integer, representing a PERL date/time value
102    
103    =item text
104    
105    long string; Text fields cannot be used in indexes or sorting and do not support the
106    normal syntax of filter clauses, but can be up to a billion character in length
107    
108    =item float
109    
110    double-precision floating-point number
111    
112    =item boolean
113    
114    single-bit numeric value; The value is stored as a 16-bit signed integer (for
115    compatability with certain database packages), but the only values supported are
116    0 and 1.
117    
118    =item id-string
119    
120    variable-length string, maximum 25 characters
121    
122    =item key-string
123    
124    variable-length string, maximum 40 characters
125    
126    =item name-string
127    
128    variable-length string, maximum 80 characters
129    
130    =item medium-string
131    
132    variable-length string, maximum 160 characters
133    
134    =item string
135    
136    variable-length string, maximum 255 characters
137    
138    =item hash-string
139    
140    variable-length string, maximum 22 characters
141    
142    =back
143    
144    The hash-string data type has a special meaning. The actual key passed into the loader will
145    be a string, but it will be digested into a 22-character MD5 code to save space. Although the
146    MD5 algorithm is not perfect, it is extremely unlikely two strings will have the same
147    digest. Therefore, it is presumed the keys will be unique. When the database is actually
148    in use, the hashed keys will be presented rather than the original values. For this reason,
149    they should not be used for entities where the key is meaningful.
150    
151    =head3 Global Tags
152    
153    The entire database definition must be inside a B<Database> tag. The display name of
154    the database is given by the text associated with the B<Title> tag. The display name
155    is only used in the automated documentation. It has no other effect. The entities and
156    relationships are listed inside the B<Entities> and B<Relationships> tags,
157    respectively. None of these tags have attributes.
158    
159        <Database>
160            <Title>... display title here...</Title>
161            <Entities>
162                ... entity definitions here ...
163            </Entities>
164            <Relationships>
165                ... relationship definitions here...
166            </Relationships>
167        </Database>
168    
169    Entities, relationships, indexes, and fields all allow a text tag called B<Notes>.
170    The text inside the B<Notes> tag contains comments that will appear when the database
171    documentation is generated. Within a B<Notes> tag, you may use C<[i]> and C<[/i]> for
172    italics, C<[b]> and C<[/b]> for bold, and C<[p]> for a new paragraph.
173    
174    =head3 Fields
175    
176    Both entities and relationships have fields described by B<Field> tags. A B<Field>
177    tag can have B<Notes> associated with it. The complete set of B<Field> tags for an
178    object mus be inside B<Fields> tags.
179    
180        <Entity ... >
181            <Fields>
182                ... Field tags ...
183            </Fields>
184        </Entity>
185    
186    The attributes for the B<Field> tag are as follows.
187    
188    =over 4
189    
190    =item name
191    
192    Name of the field. The field name should contain only letters, digits, and hyphens (C<->),
193    and the first character should be a letter. Most underlying databases are case-insensitive
194    with the respect to field names, so a best practice is to use lower-case letters only. Finally,
195    the name C<search-relevance> has special meaning for full-text searches and should not be
196    used as a field name.
197    
198    =item type
199    
200    Data type of the field. The legal data types are given above.
201    
202    =item relation
203    
204    Name of the relation containing the field. This should only be specified for entity
205    fields. The ERDB system does not support optional fields or multi-occurring fields
206    in the primary relation of an entity. Instead, they are put into secondary relations.
207    So, for example, in the C<Genome> entity, the C<group-name> field indicates a special
208    grouping used to select a subset of the genomes. A given genome may not be in any
209    groups or may be in multiple groups. Therefore, C<group-name> specifies a relation
210    value. The relation name specified must be a valid table name. By convention, it is
211    usually the entity name followed by a qualifying word (e.g. C<GenomeGroup>). In an
212    entity, the fields without a relation attribute are said to belong to the
213    I<primary relation>. This relation has the same name as the entity itself.
214    
215    =item searchable
216    
217    If specified, then the field is a candidate for full-text searching. A single full-text
218    index will be created for each relation with at least one searchable field in it.
219    For best results, this option should only be used for string or text fields.
220    
221    =item special
222    
223    This attribute allows the subclass to assign special meaning for certain fields.
224    The interpretation is up to the subclass itself. Currently, only entity fields
225    can have this attribute.
226    
227    =back
228    
229    =head3 Indexes
230    
231    An entity can have multiple alternate indexes associated with it. The fields must
232    all be from the same relation. The alternate indexes assist in ordering results
233    from a query. A relationship can have up to two indexes-- a I<to-index> and a
234    I<from-index>. These order the results when crossing the relationship. For
235    example, in the relationship C<HasContig> from C<Genome> to C<Contig>, the
236    from-index would order the contigs of a ganome, and the to-index would order
237    the genomes of a contig. A relationship's index must specify only fields in
238    the relationship.
239    
240    The indexes for an entity must be listed inside the B<Indexes> tag. The from-index
241    of a relationship is specified using the B<FromIndex> tag; the to-index is specified
242    using the B<ToIndex> tag.
243    
244    Each index can contain a B<Notes> tag. In addition, it will have an B<IndexFields>
245    tag containing the B<IndexField> tags. These specify, in order, the fields used in
246    the index. The attributes of an B<IndexField> tag are as follows.
247    
248    =over 4
249    
250    =item name
251    
252    Name of the field.
253    
254    =item order
255    
256    Sort order of the field-- C<ascending> or C<descending>.
257    
258    =back
259    
260    The B<Index>, B<FromIndex>, and B<ToIndex> tags themselves have no attributes.
261    
262    =head3 Object and Field Names
263    
264    By convention entity and relationship names use capital casing (e.g. C<Genome> or
265    C<HasRegionsIn>. Most underlying databases, however, are aggressively case-insensitive
266    with respect to relation names, converting them internally to all-upper case or
267    all-lower case.
268    
269    If syntax or parsing errors occur when you try to load or use an ERDB database, the
270    most likely reason is that one of your objects has an SQL reserved word as its name.
271    The list of SQL reserved words keeps increasing; however, most are unlikely to show
272    up as a noun or declarative verb phrase. The exceptions are C<Group>, C<User>,
273    C<Table>, C<Index>, C<Object>, C<Date>, C<Number>, C<Update>, C<Time>, C<Percent>,
274    C<Memo>, C<Order>, and C<Sum>. This problem can crop up in field names as well.
275    
276    Every entity has a field called C<id> that acts as its primary key. Every relationship
277    has fields called C<from-link> and C<to-link> that contain copies of the relevant
278    entity IDs. These are essentially ERDB's reserved words, and should not be used
279    for user-defined field names.
280    
281    =head3 Entities
282    
283    An entity is described by the B<Entity> tag. The entity can contain B<Notes>, an
284    B<Indexes> tag containing one or more secondary indexes, and a B<Fields> tag
285    containing one or more fields. The attributes of the B<Entity> tag are as follows.
286    
287    =over 4
288    
289    =item name
290    
291    Name of the entity. The entity name, by convention, uses capital casing (e.g. C<Genome>
292    or C<GroupBlock>) and should be a noun or noun phrase.
293    
294    =item keyType
295    
296    Data type of the primary key. The primary key is always named C<id>.
297    
298    =back
299    
300    =head3 Relationships
301    
302    A relationship is described by the C<Relationship> tag. Within a relationship,
303    there can be a C<Notes> tag, a C<Fields> tag containing the intersection data
304    fields, a C<FromIndex> tag containing the from-index, and a C<ToIndex> tag containing
305    the to-index.
306    
307    The C<Relationship> tag has the following attributes.
308    
309    =over 4
310    
311    =item name
312    
313    Name of the relationship. The relationship name, by convention, uses capital casing
314    (e.g. C<ContainsRegionIn> or C<HasContig>), and should be a declarative verb
315    phrase, designed to fit between the from-entity and the to-entity (e.g.
316    Block C<ContainsRegionIn> Genome).
317    
318    =item from
319    
320    Name of the entity from which the relationship starts.
321    
322    =item to
323    
324    Name of the entity to which the relationship proceeds.
325    
326    =item arity
327    
328    Relationship type: C<1M> for one-to-many and C<MM> for many-to-many.
329    
330    =back
331    
332  =cut  =cut
333    
# Line 75  Line 335 
335    
336  # Table of information about our datatypes. "sqlType" is the corresponding SQL datatype string.  # Table of information about our datatypes. "sqlType" is the corresponding SQL datatype string.
337  # "maxLen" is the maximum permissible length of the incoming string data used to populate a field  # "maxLen" is the maximum permissible length of the incoming string data used to populate a field
338  # of the specified type. "dataGen" is PERL string that will be evaluated if no test data generation  # of the specified type. "avgLen" is the average byte length for estimating
339   #string is specified in the field definition.  # record sizes. "sort" is the key modifier for the sort command, "notes" is a type description,
340  my %TypeTable = ( char =>        { sqlType => 'CHAR(1)',                        maxLen => 1,                    dataGen => "StringGen('A')" },  # and "indexMod", if non-zero, is the number of characters to use when the field is specified in an
341                                    int =>         { sqlType => 'INTEGER',                        maxLen => 20,                   dataGen => "IntGen(0, 99999999)" },  # index
342                                    string =>  { sqlType => 'VARCHAR(255)',               maxLen => 255,                  dataGen => "StringGen(IntGen(10,250))" },  my %TypeTable = ( char =>    { sqlType => 'CHAR(1)',            maxLen => 1,            avgLen =>   1, sort => "",
343                                    text =>        { sqlType => 'TEXT',                           maxLen => 1000000000,   dataGen => "StringGen(IntGen(80,1000))" },                                 indexMod =>   0, notes => "single ASCII character"},
344                                    date =>        { sqlType => 'BIGINT',                         maxLen => 80,                   dataGen => "DateGen(-7, 7, IntGen(0,1400))" },                    int =>     { sqlType => 'INTEGER',            maxLen => 20,           avgLen =>   4, sort => "n",
345                                    float =>       { sqlType => 'DOUBLE PRECISION',       maxLen => 40,                   dataGen => "FloatGen(0.0, 100.0)" },                                 indexMod =>   0, notes => "signed 32-bit integer"},
346                                    boolean => { sqlType => 'SMALLINT',                   maxLen => 1,                    dataGen => "IntGen(0, 1)" },                    counter => { sqlType => 'INTEGER UNSIGNED',   maxLen => 20,           avgLen =>   4, sort => "n",
347                                   indexMod =>   0, notes => "unsigned 32-bit integer"},
348                      string =>  { sqlType => 'VARCHAR(255)',       maxLen => 255,          avgLen => 100, sort => "",
349                                   indexMod =>   0, notes => "character string, 0 to 255 characters"},
350                      text =>    { sqlType => 'TEXT',               maxLen => 1000000000,   avgLen => 500, sort => "",
351                                   indexMod => 255, notes => "character string, nearly unlimited length, only first 255 characters are indexed"},
352                      date =>    { sqlType => 'BIGINT',             maxLen => 80,           avgLen =>   8, sort => "n",
353                                   indexMod =>   0, notes => "signed, 64-bit integer"},
354                      float =>   { sqlType => 'DOUBLE PRECISION',   maxLen => 40,           avgLen =>   8, sort => "g",
355                                   indexMod =>   0, notes => "64-bit double precision floating-point number"},
356                      boolean => { sqlType => 'SMALLINT',           maxLen => 1,            avgLen =>   1, sort => "n",
357                                   indexMod =>   0, notes => "boolean value: 0 if false, 1 if true"},
358                     'hash-string' =>
359                                 { sqlType => 'VARCHAR(22)',        maxLen => 22,           avgLen =>  22, sort => "",
360                                   indexMod =>   0, notes => "string stored in digested form, used for certain types of key fields"},
361                     'id-string' =>
362                                 { sqlType => 'VARCHAR(25)',        maxLen => 25,           avgLen =>  25, sort => "",
363                                   indexMod =>   0, notes => "character string, 0 to 25 characters"},
364                               'key-string' =>                               'key-string' =>
365                                                           { sqlType => 'VARCHAR(40)',            maxLen => 40,                   dataGen => "StringGen(IntGen(10,40))" },                               { sqlType => 'VARCHAR(40)',        maxLen => 40,           avgLen =>  10, sort => "",
366                                   indexMod =>   0, notes => "character string, 0 to 40 characters"},
367                                   'name-string' =>                                   'name-string' =>
368                                                           { sqlType => 'VARCHAR(80)',            maxLen => 80,                   dataGen => "StringGen(IntGen(10,80))" },                               { sqlType => 'VARCHAR(80)',        maxLen => 80,           avgLen =>  40, sort => "",
369                                   indexMod =>   0, notes => "character string, 0 to 80 characters"},
370                                   'medium-string' =>                                   'medium-string' =>
371                                                           { sqlType => 'VARCHAR(160)',           maxLen => 160,                  dataGen => "StringGen(IntGen(10,160))" },                               { sqlType => 'VARCHAR(160)',       maxLen => 160,          avgLen =>  40, sort => "",
372                                   indexMod =>   0, notes => "character string, 0 to 160 characters"},
373                                  );                                  );
374    
375  # Table translating arities into natural language.  # Table translating arities into natural language.
# Line 98  Line 378 
378                                     'MM' => 'many-to-many'                                     'MM' => 'many-to-many'
379                                   );                                   );
380    
381  # Table for interpreting string patterns.  # Options for XML input and output.
382    
383    my %XmlOptions = (GroupTags =>  { Relationships => 'Relationship',
384                                      Entities => 'Entity',
385                                      Fields => 'Field',
386                                      Indexes => 'Index',
387                                      IndexFields => 'IndexField'
388                                    },
389                      KeyAttr =>    { Relationship => 'name',
390                                      Entity => 'name',
391                                      Field => 'name'
392                                    },
393                      SuppressEmpty => 1,
394                     );
395    
396  my %PictureTable = ( 'A' => "abcdefghijklmnopqrstuvwxyz",  my %XmlInOpts  = (
397                                           '9' => "0123456789",                    ForceArray => ['Field', 'Index', 'IndexField'],
398                                           'X' => "abcdefghijklmnopqrstuvwxyz0123456789",                    ForceContent => 1,
399                                           'V' => "aeiou",                    NormalizeSpace => 2,
                                          'K' => "bcdfghjklmnoprstvwxyz"  
400                                     );                                     );
401    my %XmlOutOpts = (
402                      RootName => 'Database',
403                      XMLDecl => 1,
404                     );
405    
406    
407  =head2 Public Methods  =head2 Public Methods
408    
# Line 145  Line 442 
442    
443  =head3 ShowMetaData  =head3 ShowMetaData
444    
445  C<< $database->ShowMetaData($fileName); >>  C<< $erdb->ShowMetaData($fileName); >>
446    
447  This method outputs a description of the database. This description can be used to help users create  This method outputs a description of the database. This description can be used to help users create
448  the data to be loaded into the relations.  the data to be loaded into the relations.
# Line 176  Line 473 
473          # Write the HTML heading stuff.          # Write the HTML heading stuff.
474          print HTMLOUT "<html>\n<head>\n<title>$title</title>\n";          print HTMLOUT "<html>\n<head>\n<title>$title</title>\n";
475          print HTMLOUT "</head>\n<body>\n";          print HTMLOUT "</head>\n<body>\n";
476        # Write the documentation.
477        print HTMLOUT $self->DisplayMetaData();
478        # Close the document.
479        print HTMLOUT "</body>\n</html>\n";
480        # Close the file.
481        close HTMLOUT;
482    }
483    
484    =head3 DisplayMetaData
485    
486    C<< my $html = $erdb->DisplayMetaData(); >>
487    
488    Return an HTML description of the database. This description can be used to help users create
489    the data to be loaded into the relations and form queries. The output is raw includable HTML
490    without any HEAD or BODY tags.
491    
492    =over 4
493    
494    =item filename
495    
496    The name of the output file.
497    
498    =back
499    
500    =cut
501    
502    sub DisplayMetaData {
503        # Get the parameters.
504        my ($self) = @_;
505        # Get the metadata and the title string.
506        my $metadata = $self->{_metaData};
507        # Get the title string.
508        my $title = $metadata->{Title};
509        # Get the entity and relationship lists.
510        my $entityList = $metadata->{Entities};
511        my $relationshipList = $metadata->{Relationships};
512        # Declare the return variable.
513        my $retVal = "";
514        # Open the output file.
515        Trace("Building MetaData table of contents.") if T(4);
516          # Here we do the table of contents. It starts as an unordered list of section names. Each          # Here we do the table of contents. It starts as an unordered list of section names. Each
517          # section contains an ordered list of entity or relationship subsections.          # section contains an ordered list of entity or relationship subsections.
518          print HTMLOUT "<ul>\n<li><a href=\"#EntitiesSection\">Entities</a>\n<ol>\n";      $retVal .= "<ul>\n<li><a href=\"#EntitiesSection\">Entities</a>\n<ol>\n";
519          # Loop through the Entities, displaying a list item for each.          # Loop through the Entities, displaying a list item for each.
520          foreach my $key (sort keys %{$entityList}) {          foreach my $key (sort keys %{$entityList}) {
521                  # Display this item.                  # Display this item.
522                  print HTMLOUT "<li><a href=\"#$key\">$key</a></li>\n";          $retVal .= "<li><a href=\"#$key\">$key</a></li>\n";
523          }          }
524          # Close off the entity section and start the relationship section.          # Close off the entity section and start the relationship section.
525          print HTMLOUT "</ol></li>\n<li><a href=\"#RelationshipsSection\">Relationships</a>\n<ol>\n";      $retVal .= "</ol></li>\n<li><a href=\"#RelationshipsSection\">Relationships</a>\n<ol>\n";
526          # Loop through the Relationships.          # Loop through the Relationships.
527          foreach my $key (sort keys %{$relationshipList}) {          foreach my $key (sort keys %{$relationshipList}) {
528                  # Display this item.                  # Display this item.
529                  my $relationshipTitle = _ComputeRelationshipSentence($key, $relationshipList->{$key});                  my $relationshipTitle = _ComputeRelationshipSentence($key, $relationshipList->{$key});
530                  print HTMLOUT "<li><a href=\"#$key\">$relationshipTitle</a></li>\n";          $retVal .= "<li><a href=\"#$key\">$relationshipTitle</a></li>\n";
531          }          }
532          # Close off the relationship section and list the join table section.          # Close off the relationship section and list the join table section.
533          print HTMLOUT "</ol></li>\n<li><a href=\"#JoinTable\">Join Table</a></li>\n";      $retVal .= "</ol></li>\n<li><a href=\"#JoinTable\">Join Table</a></li>\n";
534          # Close off the table of contents itself.          # Close off the table of contents itself.
535          print HTMLOUT "</ul>\n";      $retVal .=  "</ul>\n";
536          # Now we start with the actual data. Denote we're starting the entity section.          # Now we start with the actual data. Denote we're starting the entity section.
537          print HTMLOUT "<a name=\"EntitiesSection\"></a><h2>Entities</h2>\n";      $retVal .= "<a name=\"EntitiesSection\"></a><h2>Entities</h2>\n";
538          # Loop through the entities.          # Loop through the entities.
539          for my $key (sort keys %{$entityList}) {          for my $key (sort keys %{$entityList}) {
540                  Trace("Building MetaData entry for $key entity.") if T(4);                  Trace("Building MetaData entry for $key entity.") if T(4);
541                  # Create the entity header. It contains a bookmark and the entity name.                  # Create the entity header. It contains a bookmark and the entity name.
542                  print HTMLOUT "<a name=\"$key\"></a><h3>$key</h3>\n";          $retVal .= "<a name=\"$key\"></a><h3>$key</h3>\n";
543                  # Get the entity data.                  # Get the entity data.
544                  my $entityData = $entityList->{$key};                  my $entityData = $entityList->{$key};
545                  # If there's descriptive text, display it.                  # If there's descriptive text, display it.
546                  if (my $notes = $entityData->{Notes}) {                  if (my $notes = $entityData->{Notes}) {
547                          print HTMLOUT "<p>" . _HTMLNote($notes->{content}) . "</p>\n";              $retVal .= "<p>" . HTMLNote($notes->{content}) . "</p>\n";
548                  }                  }
549                  # Now we want a list of the entity's relationships. First, we set up the relationship subsection.                  # Now we want a list of the entity's relationships. First, we set up the relationship subsection.
550                  print HTMLOUT "<h4>Relationships for <b>$key</b></h4>\n<ul>\n";          $retVal .= "<h4>Relationships for <b>$key</b></h4>\n<ul>\n";
551                  # Loop through the relationships.                  # Loop through the relationships.
552                  for my $relationship (sort keys %{$relationshipList}) {                  for my $relationship (sort keys %{$relationshipList}) {
553                          # Get the relationship data.                          # Get the relationship data.
# Line 220  Line 557 
557                                  # Get the relationship sentence and append the arity.                                  # Get the relationship sentence and append the arity.
558                                  my $relationshipDescription = _ComputeRelationshipSentence($relationship, $relationshipStructure);                                  my $relationshipDescription = _ComputeRelationshipSentence($relationship, $relationshipStructure);
559                                  # Display the relationship data.                                  # Display the relationship data.
560                                  print HTMLOUT "<li><a href=\"#$relationship\">$relationshipDescription</a></li>\n";                  $retVal .= "<li><a href=\"#$relationship\">$relationshipDescription</a></li>\n";
561                          }                          }
562                  }                  }
563                  # Close off the relationship list.                  # Close off the relationship list.
564                  print HTMLOUT "</ul>\n";          $retVal .= "</ul>\n";
565                  # Get the entity's relations.                  # Get the entity's relations.
566                  my $relationList = $entityData->{Relations};                  my $relationList = $entityData->{Relations};
567                  # Create a header for the relation subsection.                  # Create a header for the relation subsection.
568                  print HTMLOUT "<h4>Relations for <b>$key</b></h4>\n";          $retVal .= "<h4>Relations for <b>$key</b></h4>\n";
569                  # Loop through the relations, displaying them.                  # Loop through the relations, displaying them.
570                  for my $relation (sort keys %{$relationList}) {                  for my $relation (sort keys %{$relationList}) {
571                          my $htmlString = _ShowRelationTable($relation, $relationList->{$relation});                          my $htmlString = _ShowRelationTable($relation, $relationList->{$relation});
572                          print HTMLOUT $htmlString;              $retVal .= $htmlString;
573                  }                  }
574          }          }
575          # Denote we're starting the relationship section.          # Denote we're starting the relationship section.
576          print HTMLOUT "<a name=\"RelationshipsSection\"></a><h2>Relationships</h2>\n";      $retVal .= "<a name=\"RelationshipsSection\"></a><h2>Relationships</h2>\n";
577          # Loop through the relationships.          # Loop through the relationships.
578          for my $key (sort keys %{$relationshipList}) {          for my $key (sort keys %{$relationshipList}) {
579                  Trace("Building MetaData entry for $key relationship.") if T(4);                  Trace("Building MetaData entry for $key relationship.") if T(4);
# Line 244  Line 581 
581                  my $relationshipStructure = $relationshipList->{$key};                  my $relationshipStructure = $relationshipList->{$key};
582                  # Create the relationship header.                  # Create the relationship header.
583                  my $headerText = _ComputeRelationshipHeading($key, $relationshipStructure);                  my $headerText = _ComputeRelationshipHeading($key, $relationshipStructure);
584                  print HTMLOUT "<h3><a name=\"$key\"></a>$headerText</h3>\n";          $retVal .= "<h3><a name=\"$key\"></a>$headerText</h3>\n";
585                  # Get the entity names.                  # Get the entity names.
586                  my $fromEntity = $relationshipStructure->{from};                  my $fromEntity = $relationshipStructure->{from};
587                  my $toEntity = $relationshipStructure->{to};                  my $toEntity = $relationshipStructure->{to};
# Line 254  Line 591 
591                  # since both sentences will say the same thing.                  # since both sentences will say the same thing.
592                  my $arity = $relationshipStructure->{arity};                  my $arity = $relationshipStructure->{arity};
593                  if ($arity eq "11") {                  if ($arity eq "11") {
594                          print HTMLOUT "<p>Each <b>$fromEntity</b> relates to at most one <b>$toEntity</b>.\n";              $retVal .= "<p>Each <b>$fromEntity</b> relates to at most one <b>$toEntity</b>.\n";
595                  } else {                  } else {
596                          print HTMLOUT "<p>Each <b>$fromEntity</b> relates to multiple <b>$toEntity</b>s.\n";              $retVal .= "<p>Each <b>$fromEntity</b> relates to multiple <b>$toEntity</b>s.\n";
597                          if ($arity eq "MM" && $fromEntity ne $toEntity) {                          if ($arity eq "MM" && $fromEntity ne $toEntity) {
598                                  print HTMLOUT "Each <b>$toEntity</b> relates to multiple <b>$fromEntity</b>s.\n";                  $retVal .= "Each <b>$toEntity</b> relates to multiple <b>$fromEntity</b>s.\n";
599                          }                          }
600                  }                  }
601                  print HTMLOUT "</p>\n";          $retVal .= "</p>\n";
602                  # If there are notes on this relationship, display them.                  # If there are notes on this relationship, display them.
603                  if (my $notes = $relationshipStructure->{Notes}) {                  if (my $notes = $relationshipStructure->{Notes}) {
604                          print HTMLOUT "<p>" . _HTMLNote($notes->{content}) . "</p>\n";              $retVal .= "<p>" . HTMLNote($notes->{content}) . "</p>\n";
605                  }                  }
606                  # Generate the relationship's relation table.                  # Generate the relationship's relation table.
607                  my $htmlString = _ShowRelationTable($key, $relationshipStructure->{Relations}->{$key});                  my $htmlString = _ShowRelationTable($key, $relationshipStructure->{Relations}->{$key});
608                  print HTMLOUT $htmlString;          $retVal .= $htmlString;
609          }          }
610          Trace("Building MetaData join table.") if T(4);          Trace("Building MetaData join table.") if T(4);
611          # Denote we're starting the join table.          # Denote we're starting the join table.
612          print HTMLOUT "<a name=\"JoinTable\"></a><h3>Join Table</h3>\n";      $retVal .= "<a name=\"JoinTable\"></a><h3>Join Table</h3>\n";
613          # Create a table header.          # Create a table header.
614          print HTMLOUT _OpenTable("Join Table", "Source", "Target", "Join Condition");      $retVal .= _OpenTable("Join Table", "Source", "Target", "Join Condition");
615          # Loop through the joins.          # Loop through the joins.
616          my $joinTable = $metadata->{Joins};          my $joinTable = $metadata->{Joins};
617          my @joinKeys = keys %{$joinTable};          my @joinKeys = keys %{$joinTable};
# Line 282  Line 619 
619                  # Separate out the source, the target, and the join clause.                  # Separate out the source, the target, and the join clause.
620                  $joinKey =~ m!^([^/]+)/(.+)$!;                  $joinKey =~ m!^([^/]+)/(.+)$!;
621                  my ($sourceRelation, $targetRelation) = ($1, $2);                  my ($sourceRelation, $targetRelation) = ($1, $2);
622                  Trace("Join with key $joinKey is from $sourceRelation to $targetRelation.") if T(4);          Trace("Join with key $joinKey is from $sourceRelation to $targetRelation.") if T(Joins => 4);
623                  my $source = $self->ComputeObjectSentence($sourceRelation);                  my $source = $self->ComputeObjectSentence($sourceRelation);
624                  my $target = $self->ComputeObjectSentence($targetRelation);                  my $target = $self->ComputeObjectSentence($targetRelation);
625                  my $clause = $joinTable->{$joinKey};                  my $clause = $joinTable->{$joinKey};
626                  # Display them in a table row.                  # Display them in a table row.
627                  print HTMLOUT "<tr><td>$source</td><td>$target</td><td>$clause</td></tr>\n";          $retVal .= "<tr><td>$source</td><td>$target</td><td>$clause</td></tr>\n";
628          }          }
629          # Close the table.          # Close the table.
630          print HTMLOUT _CloseTable();      $retVal .= _CloseTable();
631          # Close the document.      Trace("Built MetaData HTML.") if T(3);
632          print HTMLOUT "</body>\n</html>\n";      # Return the HTML.
633          # Close the file.      return $retVal;
         close HTMLOUT;  
         Trace("Built MetaData web page.") if T(3);  
634  }  }
635    
636  =head3 DumpMetaData  =head3 DumpMetaData
637    
638  C<< $database->DumpMetaData(); >>  C<< $erdb->DumpMetaData(); >>
639    
640  Return a dump of the metadata structure.  Return a dump of the metadata structure.
641    
# Line 313  Line 648 
648          return Data::Dumper::Dumper($self->{_metaData});          return Data::Dumper::Dumper($self->{_metaData});
649  }  }
650    
651    =head3 FindIndexForEntity
652    
653    C<< my $indexFound = ERDB::FindIndexForEntity($xml, $entityName, $attributeName); >>
654    
655    This method locates the entry in an entity's index list that begins with the
656    specified attribute name. If the entity has no index list, one will be
657    created. This method works on raw XML, not a live ERDB object.
658    
659    =over 4
660    
661    =item xml
662    
663    The raw XML structure defining the database.
664    
665    =item entityName
666    
667    The name of the relevant entity.
668    
669    =item attributeName
670    
671    The name of the attribute relevant to the search.
672    
673    =item RETURN
674    
675    The numerical index in the index list of the index entry for the specified entity and
676    attribute, or C<undef> if no such index exists.
677    
678    =back
679    
680    =cut
681    
682    sub FindIndexForEntity {
683        # Get the parameters.
684        my ($xml, $entityName, $attributeName) = @_;
685        # Declare the return variable.
686        my $retVal;
687        # Get the named entity.
688        my $entityData = $xml->{Entities}->{$entityName};
689        if (! $entityData) {
690            Confess("Entity $entityName not found in DBD structure.");
691        } else {
692            # Insure it has an index list.
693            if (! exists $entityData->{Indexes}) {
694                $entityData->{Indexes} = [];
695            } else {
696                # Search for the desired index.
697                my $indexList = $entityData->{Indexes};
698                my $n = scalar @{$indexList};
699                Trace("Searching $n indexes in index list for $entityName.") if T(2);
700                # We use an indexed FOR here because we're returning an
701                # index number instead of an object. We do THAT so we can
702                # delete the index from the list if needed.
703                for (my $i = 0; $i < $n && !defined($retVal); $i++) {
704                    my $index = $indexList->[$i];
705                    my $fields = $index->{IndexFields};
706                    # Technically this IF should be safe (that is, we are guaranteed
707                    # the existence of a "$fields->[0]"), because when we load the XML
708                    # we have SuppressEmpty specified.
709                    if ($fields->[0]->{name} eq $attributeName) {
710                        $retVal = $i;
711                    }
712                }
713            }
714        }
715        Trace("Index for $attributeName of $entityName found at position $retVal.") if defined($retVal) && T(3);
716        Trace("Index for $attributeName not found in $entityName.") if !defined($retVal) && T(3);
717        # Return the result.
718        return $retVal;
719    }
720    
721  =head3 CreateTables  =head3 CreateTables
722    
723  C<< $datanase->CreateTables(); >>  C<< $erdb->CreateTables(); >>
724    
725  This method creates the tables for the database from the metadata structure loaded by the  This method creates the tables for the database from the metadata structure loaded by the
726  constructor. It is expected this function will only be used on rare occasions, when the  constructor. It is expected this function will only be used on rare occasions, when the
# Line 327  Line 732 
732  sub CreateTables {  sub CreateTables {
733          # Get the parameters.          # Get the parameters.
734          my ($self) = @_;          my ($self) = @_;
735          my $metadata = $self->{_metaData};      # Get the relation names.
736          my $dbh = $self->{_dbh};      my @relNames = $self->GetTableNames();
737          # Loop through the entities.      # Loop through the relations.
738          my $entityHash = $metadata->{Entities};      for my $relationName (@relNames) {
         for my $entityName (keys %{$entityHash}) {  
                 my $entityData = $entityHash->{$entityName};  
                 # Tell the user what we're doing.  
                 Trace("Creating relations for entity $entityName.") if T(1);  
                 # Loop through the entity's relations.  
                 for my $relationName (keys %{$entityData->{Relations}}) {  
739                          # Create a table for this relation.                          # Create a table for this relation.
740                          $self->CreateTable($relationName);                          $self->CreateTable($relationName);
741                          Trace("Relation $relationName created.") if T(1);          Trace("Relation $relationName created.") if T(2);
                 }  
         }  
         # Loop through the relationships.  
         my $relationshipTable = $metadata->{Relationships};  
         for my $relationshipName (keys %{$metadata->{Relationships}}) {  
                 # Create a table for this relationship.  
                 Trace("Creating relationship $relationshipName.") if T(1);  
                 $self->CreateTable($relationshipName);  
742          }          }
743  }  }
744    
745  =head3 CreateTable  =head3 CreateTable
746    
747  C<< $database->CreateTable($tableName, $indexFlag); >>  C<< $erdb->CreateTable($tableName, $indexFlag, $estimatedRows); >>
748    
749  Create the table for a relation and optionally create its indexes.  Create the table for a relation and optionally create its indexes.
750    
# Line 363  Line 754 
754    
755  Name of the relation (which will also be the table name).  Name of the relation (which will also be the table name).
756    
757  =item $indexFlag  =item indexFlag
758    
759  TRUE if the indexes for the relation should be created, else FALSE. If FALSE,  TRUE if the indexes for the relation should be created, else FALSE. If FALSE,
760  L</CreateIndexes> must be called later to bring the indexes into existence.  L</CreateIndexes> must be called later to bring the indexes into existence.
761    
762    =item estimatedRows (optional)
763    
764    If specified, the estimated maximum number of rows for the relation. This
765    information allows the creation of tables using storage engines that are
766    faster but require size estimates, such as MyISAM.
767    
768  =back  =back
769    
770  =cut  =cut
771    
772  sub CreateTable {  sub CreateTable {
773          # Get the parameters.          # Get the parameters.
774          my ($self, $relationName, $indexFlag) = @_;      my ($self, $relationName, $indexFlag, $estimatedRows) = @_;
775          # Get the database handle.          # Get the database handle.
776          my $dbh = $self->{_dbh};          my $dbh = $self->{_dbh};
777          # Get the relation data and determine whether or not the relation is primary.          # Get the relation data and determine whether or not the relation is primary.
# Line 398  Line 795 
795          # Insure the table is not already there.          # Insure the table is not already there.
796          $dbh->drop_table(tbl => $relationName);          $dbh->drop_table(tbl => $relationName);
797          Trace("Table $relationName dropped.") if T(2);          Trace("Table $relationName dropped.") if T(2);
798        # If there are estimated rows, create an estimate so we can take advantage of
799        # faster DB technologies.
800        my $estimation = undef;
801        if ($estimatedRows) {
802            $estimation = [$self->EstimateRowSize($relationName), $estimatedRows];
803        }
804          # Create the table.          # Create the table.
805          Trace("Creating table $relationName: $fieldThing") if T(2);          Trace("Creating table $relationName: $fieldThing") if T(2);
806          $dbh->create_table(tbl => $relationName, flds => $fieldThing);      $dbh->create_table(tbl => $relationName, flds => $fieldThing, estimates => $estimation);
807          Trace("Relation $relationName created in database.") if T(2);          Trace("Relation $relationName created in database.") if T(2);
808          # If we want to build the indexes, we do it here.      # If we want to build the indexes, we do it here. Note that the full-text search
809        # index will not be built until the table has been loaded.
810          if ($indexFlag) {          if ($indexFlag) {
811                  $self->CreateIndex($relationName);                  $self->CreateIndex($relationName);
812          }          }
813  }  }
814    
815    =head3 VerifyFields
816    
817    C<< my $count = $erdb->VerifyFields($relName, \@fieldList); >>
818    
819    Run through the list of proposed field values, insuring that all the character fields are
820    below the maximum length. If any fields are too long, they will be truncated in place.
821    
822    =over 4
823    
824    =item relName
825    
826    Name of the relation for which the specified fields are destined.
827    
828    =item fieldList
829    
830    Reference to a list, in order, of the fields to be put into the relation.
831    
832    =item RETURN
833    
834    Returns the number of fields truncated.
835    
836    =back
837    
838    =cut
839    
840    sub VerifyFields {
841        # Get the parameters.
842        my ($self, $relName, $fieldList) = @_;
843        # Initialize the return value.
844        my $retVal = 0;
845        # Get the relation definition.
846        my $relData = $self->_FindRelation($relName);
847        # Get the list of field descriptors.
848        my $fieldTypes = $relData->{Fields};
849        my $fieldCount = scalar @{$fieldTypes};
850        # Loop through the two lists.
851        for (my $i = 0; $i < $fieldCount; $i++) {
852            # Get the type of the current field.
853            my $fieldType = $fieldTypes->[$i]->{type};
854            # If it's a character field, verify the length.
855            if ($fieldType =~ /string/) {
856                my $maxLen = $TypeTable{$fieldType}->{maxLen};
857                my $oldString = $fieldList->[$i];
858                if (length($oldString) > $maxLen) {
859                    # Here it's too big, so we truncate it.
860                    Trace("Truncating field $i in relation $relName to $maxLen characters from \"$oldString\".") if T(1);
861                    $fieldList->[$i] = substr $oldString, 0, $maxLen;
862                    $retVal++;
863                }
864            }
865        }
866        # Return the truncation count.
867        return $retVal;
868    }
869    
870    =head3 DigestFields
871    
872    C<< $erdb->DigestFields($relName, $fieldList); >>
873    
874    Digest the strings in the field list that correspond to data type C<hash-string> in the
875    specified relation.
876    
877    =over 4
878    
879    =item relName
880    
881    Name of the relation to which the fields belong.
882    
883    =item fieldList
884    
885    List of field contents to be loaded into the relation.
886    
887    =back
888    
889    =cut
890    #: Return Type ;
891    sub DigestFields {
892        # Get the parameters.
893        my ($self, $relName, $fieldList) = @_;
894        # Get the relation definition.
895        my $relData = $self->_FindRelation($relName);
896        # Get the list of field descriptors.
897        my $fieldTypes = $relData->{Fields};
898        my $fieldCount = scalar @{$fieldTypes};
899        # Loop through the two lists.
900        for (my $i = 0; $i < $fieldCount; $i++) {
901            # Get the type of the current field.
902            my $fieldType = $fieldTypes->[$i]->{type};
903            # If it's a hash string, digest it in place.
904            if ($fieldType eq 'hash-string') {
905                $fieldList->[$i] = $self->DigestKey($fieldList->[$i]);
906            }
907        }
908    }
909    
910    =head3 DigestKey
911    
912    C<< my $digested = $erdb->DigestKey($keyValue); >>
913    
914    Return the digested value of a symbolic key. The digested value can then be plugged into a
915    key-based search into a table with key-type hash-string.
916    
917    Currently the digesting process is independent of the database structure, but that may not
918    always be the case, so this is an instance method instead of a static method.
919    
920    =over 4
921    
922    =item keyValue
923    
924    Key value to digest.
925    
926    =item RETURN
927    
928    Digested value of the key.
929    
930    =back
931    
932    =cut
933    
934    sub DigestKey {
935        # Get the parameters.
936        my ($self, $keyValue) = @_;
937        # Compute the digest.
938        my $retVal = md5_base64($keyValue);
939        # Return the result.
940        return $retVal;
941    }
942    
943  =head3 CreateIndex  =head3 CreateIndex
944    
945  C<< $database->CreateIndex($relationName); >>  C<< $erdb->CreateIndex($relationName); >>
946    
947  Create the indexes for a relation. If a table is being loaded from a large source file (as  Create the indexes for a relation. If a table is being loaded from a large source file (as
948  is the case in L</LoadTable>), it is best to create the indexes after the load. If that is  is the case in L</LoadTable>), it is sometimes best to create the indexes after the load.
949  the case, then L</CreateTable> should be called with the index flag set to FALSE, and this  If that is the case, then L</CreateTable> should be called with the index flag set to
950  method used after the load to create the indexes for the table.  FALSE, and this method used after the load to create the indexes for the table.
951    
952  =cut  =cut
953    
# Line 431  Line 963 
963          for my $indexName (keys %{$indexHash}) {          for my $indexName (keys %{$indexHash}) {
964                  my $indexData = $indexHash->{$indexName};                  my $indexData = $indexHash->{$indexName};
965                  # Get the index's field list.                  # Get the index's field list.
966                  my @fieldList = _FixNames(@{$indexData->{IndexFields}});          my @rawFields = @{$indexData->{IndexFields}};
967            # Get a hash of the relation's field types.
968            my %types = map { $_->{name} => $_->{type} } @{$relationData->{Fields}};
969            # We need to check for text fields. We need a append a length limitation for them. To do
970            # that, we need the relation's field list.
971            my $relFields = $relationData->{Fields};
972            for (my $i = 0; $i <= $#rawFields; $i++) {
973                # Get the field type.
974                my $field = $rawFields[$i];
975                my $type = $types{$field};
976                # Ask if it requires using prefix notation for the index.
977                my $mod = $TypeTable{$type}->{indexMod};
978                Trace("Field $field ($i) in $relationName has type $type and indexMod $mod.") if T(3);
979                if ($mod) {
980                    # Append the prefix length to the field name,
981                    $rawFields[$i] .= "($mod)";
982                }
983            }
984            my @fieldList = _FixNames(@rawFields);
985                  my $flds = join(', ', @fieldList);                  my $flds = join(', ', @fieldList);
986                  # Get the index's uniqueness flag.                  # Get the index's uniqueness flag.
987                  my $unique = (exists $indexData->{Unique} ? $indexData->{Unique} : 'false');          my $unique = (exists $indexData->{Unique} ? 'unique' : undef);
988                  # Create the index.                  # Create the index.
989                  $dbh->create_index(idx => $indexName, tbl => $relationName, flds => $flds, unique => $unique);          my $rv = $dbh->create_index(idx => $indexName, tbl => $relationName,
990                                        flds => $flds, kind => $unique);
991            if ($rv) {
992                  Trace("Index created: $indexName for $relationName ($flds)") if T(1);                  Trace("Index created: $indexName for $relationName ($flds)") if T(1);
993            } else {
994                Confess("Error creating index $indexName for $relationName using ($flds): " . $dbh->error_message());
995            }
996          }          }
997  }  }
998    
999  =head3 LoadTables  =head3 GetSecondaryFields
1000    
1001  C<< my $stats = $database->LoadTables($directoryName, $rebuild); >>  C<< my %fieldTuples = $erdb->GetSecondaryFields($entityName); >>
1002    
1003  This method will load the database tables from a directory. The tables must already have been created  This method will return a list of the name and type of each of the secondary
1004  in the database. (This can be done by calling L</CreateTables>.) The caller passes in a directory name;  fields for a specified entity. Secondary fields are stored in two-column tables
1005    in addition to the primary entity table. This enables the field to have no value
1006    or to have multiple values.
1007    
1008    =over 4
1009    
1010    =item entityName
1011    
1012    Name of the entity whose secondary fields are desired.
1013    
1014    =item RETURN
1015    
1016    Returns a hash mapping the field names to their field types.
1017    
1018    =back
1019    
1020    =cut
1021    
1022    sub GetSecondaryFields {
1023        # Get the parameters.
1024        my ($self, $entityName) = @_;
1025        # Declare the return variable.
1026        my %retVal = ();
1027        # Look for the entity.
1028        my $table = $self->GetFieldTable($entityName);
1029        # Loop through the fields, pulling out the secondaries.
1030        for my $field (sort keys %{$table}) {
1031            if ($table->{$field}->{relation} ne $entityName) {
1032                # Here we have a secondary field.
1033                $retVal{$field} = $table->{$field}->{type};
1034            }
1035        }
1036        # Return the result.
1037        return %retVal;
1038    }
1039    
1040    =head3 GetFieldRelationName
1041    
1042    C<< my $name = $erdb->GetFieldRelationName($objectName, $fieldName); >>
1043    
1044    Return the name of the relation containing a specified field.
1045    
1046    =over 4
1047    
1048    =item objectName
1049    
1050    Name of the entity or relationship containing the field.
1051    
1052    =item fieldName
1053    
1054    Name of the relevant field in that entity or relationship.
1055    
1056    =item RETURN
1057    
1058    Returns the name of the database relation containing the field, or C<undef> if
1059    the field does not exist.
1060    
1061    =back
1062    
1063    =cut
1064    
1065    sub GetFieldRelationName {
1066        # Get the parameters.
1067        my ($self, $objectName, $fieldName) = @_;
1068        # Declare the return variable.
1069        my $retVal;
1070        # Get the object field table.
1071        my $table = $self->GetFieldTable($objectName);
1072        # Only proceed if the field exists.
1073        if (exists $table->{$fieldName}) {
1074            # Determine the name of the relation that contains this field.
1075            $retVal = $table->{$fieldName}->{relation};
1076        }
1077        # Return the result.
1078        return $retVal;
1079    }
1080    
1081    =head3 DeleteValue
1082    
1083    C<< my $numDeleted = $erdb->DeleteValue($entityName, $id, $fieldName, $fieldValue); >>
1084    
1085    Delete secondary field values from the database. This method can be used to delete all
1086    values of a specified field for a particular entity instance, or only a single value.
1087    
1088    Secondary fields are stored in two-column relations separate from an entity's primary
1089    table, and as a result a secondary field can legitimately have no value or multiple
1090    values. Therefore, it makes sense to talk about deleting secondary fields where it
1091    would not make sense for primary fields.
1092    
1093    =over 4
1094    
1095    =item entityName
1096    
1097    Name of the entity from which the fields are to be deleted.
1098    
1099    =item id
1100    
1101    ID of the entity instance to be processed. If the instance is not found, this
1102    method will have no effect.
1103    
1104    =item fieldName
1105    
1106    Name of the field whose values are to be deleted.
1107    
1108    =item fieldValue (optional)
1109    
1110    Value to be deleted. If not specified, then all values of the specified field
1111    will be deleted for the entity instance. If specified, then only the values which
1112    match this parameter will be deleted.
1113    
1114    =item RETURN
1115    
1116    Returns the number of rows deleted.
1117    
1118    =back
1119    
1120    =cut
1121    
1122    sub DeleteValue {
1123        # Get the parameters.
1124        my ($self, $entityName, $id, $fieldName, $fieldValue) = @_;
1125        # Declare the return value.
1126        my $retVal = 0;
1127        # We need to set up an SQL command to do the deletion. First, we
1128        # find the name of the field's relation.
1129        my $table = $self->GetFieldTable($entityName);
1130        my $field = $table->{$fieldName};
1131        my $relation = $field->{relation};
1132        # Make sure this is a secondary field.
1133        if ($relation eq $entityName) {
1134            Confess("Cannot delete values of $fieldName for $entityName.");
1135        } else {
1136            # Set up the SQL command to delete all values.
1137            my $sql = "DELETE FROM $relation WHERE id = ?";
1138            my @parms = $id;
1139            # If a value has been specified, append it to the statement.
1140            if (defined $fieldValue) {
1141                $sql .= " AND $fieldName = ?";
1142                push @parms, $fieldValue;
1143            }
1144            # Execute the command.
1145            my $dbh = $self->{_dbh};
1146            $retVal = $dbh->SQL($sql, 0, @parms);
1147        }
1148        # Return the result.
1149        return $retVal;
1150    }
1151    
1152    =head3 LoadTables
1153    
1154    C<< my $stats = $erdb->LoadTables($directoryName, $rebuild); >>
1155    
1156    This method will load the database tables from a directory. The tables must already have been created
1157    in the database. (This can be done by calling L</CreateTables>.) The caller passes in a directory name;
1158  all of the relations to be loaded must have a file in the directory with the same name as the relation  all of the relations to be loaded must have a file in the directory with the same name as the relation
1159  (optionally with a suffix of C<.dtx>). Each file must be a tab-delimited table of field values. Each  (optionally with a suffix of C<.dtx>). Each file must be a tab-delimited table of field values. Each
1160  line of the file will be loaded as a row of the target relation table. The field values should be in  line of the file will be loaded as a row of the target relation table. The field values should be in
# Line 486  Line 1194 
1194          $directoryName =~ s!/\\$!!;          $directoryName =~ s!/\\$!!;
1195          # Declare the return variable.          # Declare the return variable.
1196          my $retVal = Stats->new();          my $retVal = Stats->new();
1197          # Get the metadata structure.      # Get the relation names.
1198          my $metaData = $self->{_metaData};      my @relNames = $self->GetTableNames();
1199          # Loop through the entities.      for my $relationName (@relNames) {
         for my $entity (values %{$metaData->{Entities}}) {  
                 # Loop through the entity's relations.  
                 for my $relationName (keys %{$entity->{Relations}}) {  
1200                          # Try to load this relation.                          # Try to load this relation.
1201                          my $result = $self->_LoadRelation($directoryName, $relationName, $rebuild);                          my $result = $self->_LoadRelation($directoryName, $relationName, $rebuild);
1202                          # Accumulate the statistics.                          # Accumulate the statistics.
1203                          $retVal->Accumulate($result);                          $retVal->Accumulate($result);
1204                  }                  }
         }  
         # Loop through the relationships.  
         for my $relationshipName (keys %{$metaData->{Relationships}}) {  
                 # Try to load this relationship's relation.  
                 my $result = $self->_LoadRelation($directoryName, $relationshipName, $rebuild);  
                 # Accumulate the statistics.  
                 $retVal->Accumulate($result);  
         }  
1205          # Add the duration of the load to the statistical object.          # Add the duration of the load to the statistical object.
1206          $retVal->Add('duration', gettimeofday - $startTime);          $retVal->Add('duration', gettimeofday - $startTime);
1207          # Return the accumulated statistics.          # Return the accumulated statistics.
1208          return $retVal;          return $retVal;
1209  }  }
1210    
1211    
1212  =head3 GetTableNames  =head3 GetTableNames
1213    
1214  C<< my @names = $database->GetTableNames; >>  C<< my @names = $erdb->GetTableNames; >>
1215    
1216  Return a list of the relations required to implement this database.  Return a list of the relations required to implement this database.
1217    
# Line 530  Line 1228 
1228    
1229  =head3 GetEntityTypes  =head3 GetEntityTypes
1230    
1231  C<< my @names = $database->GetEntityTypes; >>  C<< my @names = $erdb->GetEntityTypes; >>
1232    
1233  Return a list of the entity type names.  Return a list of the entity type names.
1234    
# Line 545  Line 1243 
1243          return sort keys %{$entityList};          return sort keys %{$entityList};
1244  }  }
1245    
1246    =head3 GetDataTypes
1247    
1248    C<< my %types = ERDB::GetDataTypes(); >>
1249    
1250    Return a table of ERDB data types. The table returned is a hash of hashes.
1251    The keys of the big hash are the datatypes. Each smaller hash has several
1252    values used to manage the data. The most interesting is the SQL type (key
1253    C<sqlType>) and the descriptive node (key C<notes>).
1254    
1255    Note that changing the values in the smaller hashes will seriously break
1256    things, so this data should be treated as read-only.
1257    
1258    =cut
1259    
1260    sub GetDataTypes {
1261        return %TypeTable;
1262    }
1263    
1264    
1265    =head3 IsEntity
1266    
1267    C<< my $flag = $erdb->IsEntity($entityName); >>
1268    
1269    Return TRUE if the parameter is an entity name, else FALSE.
1270    
1271    =over 4
1272    
1273    =item entityName
1274    
1275    Object name to be tested.
1276    
1277    =item RETURN
1278    
1279    Returns TRUE if the specified string is an entity name, else FALSE.
1280    
1281    =back
1282    
1283    =cut
1284    
1285    sub IsEntity {
1286        # Get the parameters.
1287        my ($self, $entityName) = @_;
1288        # Test to see if it's an entity.
1289        return exists $self->{_metaData}->{Entities}->{$entityName};
1290    }
1291    
1292  =head3 Get  =head3 Get
1293    
1294  C<< my $query = $database->Get(\@objectNames, $filterClause, $param1, $param2, ..., $paramN); >>  C<< my $query = $erdb->Get(\@objectNames, $filterClause, \@params); >>
1295    
1296  This method returns a query object for entities of a specified type using a specified filter.  This method returns a query object for entities of a specified type using a specified filter.
1297  The filter is a standard WHERE/ORDER BY clause with question marks as parameter markers and each  The filter is a standard WHERE/ORDER BY clause with question marks as parameter markers and each
# Line 555  Line 1299 
1299  following call requests all B<Genome> objects for the genus specified in the variable  following call requests all B<Genome> objects for the genus specified in the variable
1300  $genus.  $genus.
1301    
1302  C<< $query = $sprout->Get(['Genome'], "Genome(genus) = ?", $genus); >>  C<< $query = $erdb->Get(['Genome'], "Genome(genus) = ?", [$genus]); >>
1303    
1304  The WHERE clause contains a single question mark, so there is a single additional  The WHERE clause contains a single question mark, so there is a single additional
1305  parameter representing the parameter value. It would also be possible to code  parameter representing the parameter value. It would also be possible to code
1306    
1307  C<< $query = $sprout->Get(['Genome'], "Genome(genus) = \'$genus\'"); >>  C<< $query = $erdb->Get(['Genome'], "Genome(genus) = \'$genus\'"); >>
1308    
1309  however, this version of the call would generate a syntax error if there were any quote  however, this version of the call would generate a syntax error if there were any quote
1310  characters inside the variable C<$genus>.  characters inside the variable C<$genus>.
# Line 572  Line 1316 
1316  It is possible to specify multiple entity and relationship names in order to retrieve more than  It is possible to specify multiple entity and relationship names in order to retrieve more than
1317  one object's data at the same time, which allows highly complex joined queries. For example,  one object's data at the same time, which allows highly complex joined queries. For example,
1318    
1319  C<< $query = $sprout->Get(['Genome', 'ComesFrom', 'Source'], "Genome(genus) = ?", $genus); >>  C<< $query = $erdb->Get(['Genome', 'ComesFrom', 'Source'], "Genome(genus) = ?", [$genus]); >>
1320    
1321  If multiple names are specified, then the query processor will automatically determine a  If multiple names are specified, then the query processor will automatically determine a
1322  join path between the entities and relationships. The algorithm used is very simplistic.  join path between the entities and relationships. The algorithm used is very simplistic.
1323  In particular, you can't specify any entity or relationship more than once, and if a  In particular, if a relationship is recursive, the path is determined by the order in which
1324  relationship is recursive, the path is determined by the order in which the entity  the entity and the relationship appear. For example, consider a recursive relationship
1325  and the relationship appear. For example, consider a recursive relationship B<IsParentOf>  B<IsParentOf> which relates B<People> objects to other B<People> objects. If the join path is
 which relates B<People> objects to other B<People> objects. If the join path is  
1326  coded as C<['People', 'IsParentOf']>, then the people returned will be parents. If, however,  coded as C<['People', 'IsParentOf']>, then the people returned will be parents. If, however,
1327  the join path is C<['IsParentOf', 'People']>, then the people returned will be children.  the join path is C<['IsParentOf', 'People']>, then the people returned will be children.
1328    
1329    If an entity or relationship is mentioned twice, the name for the second occurrence will
1330    be suffixed with C<2>, the third occurrence will be suffixed with C<3>, and so forth. So,
1331    for example, if we have C<['Feature', 'HasContig', 'Contig', 'HasContig']>, then the
1332    B<to-link> field of the first B<HasContig> is specified as C<HasContig(to-link)>, while
1333    the B<to-link> field of the second B<HasContig> is specified as C<HasContig2(to-link)>.
1334    
1335  =over 4  =over 4
1336    
1337  =item objectNames  =item objectNames
# Line 605  Line 1354 
1354    
1355  C<< "Genome(genus) = ? ORDER BY Genome(species)" >>  C<< "Genome(genus) = ? ORDER BY Genome(species)" >>
1356    
1357    Note that the case is important. Only an uppercase "ORDER BY" with a single space will
1358    be processed. The idea is to make it less likely to find the verb by accident.
1359    
1360  The rules for field references in a sort order are the same as those for field references in the  The rules for field references in a sort order are the same as those for field references in the
1361  filter clause in general; however, odd things may happen if a sort field is from a secondary  filter clause in general; however, odd things may happen if a sort field is from a secondary
1362  relation.  relation.
1363    
1364  =item param1, param2, ..., paramN  Finally, you can limit the number of rows returned by adding a LIMIT clause. The LIMIT must
1365    be the last thing in the filter clause, and it contains only the word "LIMIT" followed by
1366    a positive number. So, for example
1367    
1368    C<< "Genome(genus) = ? ORDER BY Genome(species) LIMIT 10" >>
1369    
1370  Parameter values to be substituted into the filter clause.  will only return the first ten genomes for the specified genus. The ORDER BY clause is not
1371    required. For example, to just get the first 10 genomes in the B<Genome> table, you could
1372    use
1373    
1374    C<< "LIMIT 10" >>
1375    
1376    =item params
1377    
1378    Reference to a list of parameter values to be substituted into the filter clause.
1379    
1380  =item RETURN  =item RETURN
1381    
# Line 623  Line 1387 
1387    
1388  sub Get {  sub Get {
1389          # Get the parameters.          # Get the parameters.
1390          my ($self, $objectNames, $filterClause, @params) = @_;      my ($self, $objectNames, $filterClause, $params) = @_;
1391          # Construct the SELECT statement. The general pattern is      # Process the SQL stuff.
1392          #      my ($suffix, $mappedNameListRef, $mappedNameHashRef) =
1393          # SELECT name1.*, name2.*, ... nameN.* FROM name1, name2, ... nameN          $self->_SetupSQL($objectNames, $filterClause);
1394          #      # Create the query.
1395          my $dbh = $self->{_dbh};      my $command = "SELECT DISTINCT " . join(".*, ", @{$mappedNameListRef}) .
1396          my $command = "SELECT DISTINCT " . join('.*, ', @{$objectNames}) . ".* FROM " .          ".* $suffix";
1397                                  join(', ', @{$objectNames});      my $sth = $self->_GetStatementHandle($command, $params);
1398          # Check for a filter clause.      # Now we create the relation map, which enables DBQuery to determine the order, name
1399          if ($filterClause) {      # and mapped name for each object in the query.
1400                  # Here we have one, so we convert its field names and add it to the query. First,      my @relationMap = ();
1401                  # We create a copy of the filter string we can work with.      for my $mappedName (@{$mappedNameListRef}) {
1402                  my $filterString = $filterClause;          push @relationMap, [$mappedName, $mappedNameHashRef->{$mappedName}];
                 # Next, we sort the object names by length. This helps protect us from finding  
                 # object names inside other object names when we're doing our search and replace.  
                 my @sortedNames = sort { length($b) - length($a) } @{$objectNames};  
                 # We will also keep a list of conditions to add to the WHERE clause in order to link  
                 # entities and relationships as well as primary relations to secondary ones.  
                 my @joinWhere = ();  
                 # The final preparatory step is to create a hash table of relation names. The  
                 # table begins with the relation names already in the SELECT command.  
                 my %fromNames = ();  
                 for my $objectName (@sortedNames) {  
                         $fromNames{$objectName} = 1;  
                 }  
                 # We are ready to begin. We loop through the object names, replacing each  
                 # object name's field references by the corresponding SQL field reference.  
                 # Along the way, if we find a secondary relation, we will need to add it  
                 # to the FROM clause.  
                 for my $objectName (@sortedNames) {  
                         # Get the length of the object name plus 2. This is the value we add to the  
                         # size of the field name to determine the size of the field reference as a  
                         # whole.  
                         my $nameLength = 2 + length $objectName;  
                         # Get the object's field list.  
                         my $fieldList = $self->_GetFieldTable($objectName);  
                         # Find the field references for this object.  
                         while ($filterString =~ m/$objectName\(([^)]*)\)/g) {  
                                 # At this point, $1 contains the field name, and the current position  
                                 # is set immediately after the final parenthesis. We pull out the name of  
                                 # the field and the position and length of the field reference as a whole.  
                                 my $fieldName = $1;  
                                 my $len = $nameLength + length $fieldName;  
                                 my $pos = pos($filterString) - $len;  
                                 # Insure the field exists.  
                                 if (!exists $fieldList->{$fieldName}) {  
                                         Confess("Field $fieldName not found for object $objectName.");  
                                 } else {  
                                         # Get the field's relation.  
                                         my $relationName = $fieldList->{$fieldName}->{relation};  
                                         # Insure the relation is in the FROM clause.  
                                         if (!exists $fromNames{$relationName}) {  
                                                 # Add the relation to the FROM clause.  
                                                 $command .= ", $relationName";  
                                                 # Create its join sub-clause.  
                                                 push @joinWhere, "$objectName.id = $relationName.id";  
                                                 # Denote we have it available for future fields.  
                                                 $fromNames{$relationName} = 1;  
                                         }  
                                         # Form an SQL field reference from the relation name and the field name.  
                                         my $sqlReference = "$relationName." . _FixName($fieldName);  
                                         # Put it into the filter string in place of the old value.  
                                         substr($filterString, $pos, $len) = $sqlReference;  
                                         # Reposition the search.  
                                         pos $filterString = $pos + length $sqlReference;  
                                 }  
                         }  
                 }  
                 # The next step is to join the objects together. We only need to do this if there  
                 # is more than one object in the object list. We start with the first object and  
                 # run through the objects after it. Note also that we make a safety copy of the  
                 # list before running through it.  
                 my @objectList = @{$objectNames};  
                 my $lastObject = shift @objectList;  
                 # Get the join table.  
                 my $joinTable = $self->{_metaData}->{Joins};  
                 # Loop through the object list.  
                 for my $thisObject (@objectList) {  
                         # Look for a join.  
                         my $joinKey = "$lastObject/$thisObject";  
                         if (!exists $joinTable->{$joinKey}) {  
                                 # Here there's no join, so we throw an error.  
                                 Confess("No join exists to connect from $lastObject to $thisObject.");  
                         } else {  
                                 # Get the join clause and add it to the WHERE list.  
                                 push @joinWhere, $joinTable->{$joinKey};  
                                 # Save this object as the last object for the next iteration.  
                                 $lastObject = $thisObject;  
                         }  
                 }  
                 # Now we need to handle the whole ORDER BY thing. We'll put the order by clause  
                 # in the following variable.  
                 my $orderClause = "";  
                 # Locate the ORDER BY verb (if any).  
                 if ($filterString =~ m/^(.*)ORDER BY/g) {  
                         # Here we have an ORDER BY verb. Split it off of the filter string.  
                         my $pos = pos $filterString;  
                         $orderClause = substr($filterString, $pos);  
                         $filterString = $1;  
                 }  
                 # Add the filter and the join clauses (if any) to the SELECT command.  
                 if ($filterString) {  
                         push @joinWhere, "($filterString)";  
                 }  
                 if (@joinWhere) {  
                         $command .= " WHERE " . join(' AND ', @joinWhere);  
                 }  
                 # Add the sort clause (if any) to the SELECT command.  
                 if ($orderClause) {  
                         $command .= " ORDER BY $orderClause";  
                 }  
1403          }          }
         Trace("SQL query: $command") if T(2);  
         Trace("PARMS: '" . (join "', '", @params) . "'") if (T(3) && (@params > 0));  
         my $sth = $dbh->prepare_command($command);  
         # Execute it with the parameters bound in.  
         $sth->execute(@params) || Confess("SELECT error" . $sth->errstr());  
1404          # Return the statement object.          # Return the statement object.
1405          my $retVal = DBQuery::_new($self, $sth, @{$objectNames});      my $retVal = DBQuery::_new($self, $sth, \@relationMap);
1406          return $retVal;          return $retVal;
1407  }  }
1408    
1409  =head3 GetList  =head3 Search
   
 C<< my @dbObjects = $database->GetList(\@objectNames, $filterClause, $param1, $param2, ..., $paramN); >>  
1410    
1411  Return a list of object descriptors for the specified objects as determined by the  C<< my $query = $erdb->Search($searchExpression, $idx, \@objectNames, $filterClause, \@params); >>
 specified filter clause.  
1412    
1413  This method is essentially the same as L</Get> except it returns a list of objects rather  Perform a full text search with filtering. The search will be against a specified object
1414  that a query object that can be used to get the results one record at a time.  in the object name list. That object will get an extra field containing the search
1415    relevance. Note that except for the search expression, the parameters of this method are
1416    the same as those for L</Get> and follow the same rules.
1417    
1418  =over 4  =over 4
1419    
1420  =over 4  =item searchExpression
1421    
1422    Boolean search expression for the text fields of the target object. The default mode for
1423    a Boolean search expression is OR, but we want the default to be AND, so we will
1424    add a C<+> operator to each word with no other operator before it.
1425    
1426    =item idx
1427    
1428    Index in the I<$objectNames> list of the table to be searched in full-text mode.
1429    
1430  =item objectNames  =item objectNames
1431    
# Line 773  Line 1441 
1441  or secondary entity relations; however, all of the entities and relationships involved must  or secondary entity relations; however, all of the entities and relationships involved must
1442  be included in the list of object names.  be included in the list of object names.
1443    
1444  The filter clause can also specify a sort order. To do this, simply follow the filter string  =item params
 with an ORDER BY clause. For example, the following filter string gets all genomes for a  
 particular genus and sorts them by species name.  
1445    
1446  C<< "Genome(genus) = ? ORDER BY Genome(species)" >>  Reference to a list of parameter values to be substituted into the filter clause.
1447    
1448  The rules for field references in a sort order are the same as those for field references in the  =item RETURN
1449  filter clause in general; however, odd things may happen if a sort field is from a secondary  
1450  relation.  Returns a query object for the specified search.
1451    
1452    =back
1453    
1454    =cut
1455    
1456    sub Search {
1457        # Get the parameters.
1458        my ($self, $searchExpression, $idx, $objectNames, $filterClause, $params) = @_;
1459        # Declare the return variable.
1460        my $retVal;
1461        # Create a safety copy of the parameter list. Note we have to be careful to insure
1462        # a parameter list exists before we copy it.
1463        my @myParams = ();
1464        if (defined $params) {
1465            @myParams = @{$params};
1466        }
1467        # Get the first object's structure so we have access to the searchable fields.
1468        my $object1Name = $objectNames->[$idx];
1469        my $object1Structure = $self->_GetStructure($object1Name);
1470        # Get the field list.
1471        if (! exists $object1Structure->{searchFields}) {
1472            Confess("No searchable index for $object1Name.");
1473        } else {
1474            # Get the field list.
1475            my @fields = @{$object1Structure->{searchFields}};
1476            # Clean the search expression.
1477            my $actualKeywords = $self->CleanKeywords($searchExpression);
1478            # Prefix a "+" to each uncontrolled word. This converts the default
1479            # search mode from OR to AND.
1480            $actualKeywords =~ s/(^|\s)(\w)/$1\+$2/g;
1481            Trace("Actual keywords for search are\n$actualKeywords") if T(3);
1482            # We need two match expressions, one for the filter clause and one in the
1483            # query itself. Both will use a parameter mark, so we need to push the
1484            # search expression onto the front of the parameter list twice.
1485            unshift @myParams, $actualKeywords, $actualKeywords;
1486            # Build the match expression.
1487            my @matchFilterFields = map { "$object1Name." . _FixName($_) } @fields;
1488            my $matchClause = "MATCH (" . join(", ", @matchFilterFields) . ") AGAINST (? IN BOOLEAN MODE)";
1489            # Process the SQL stuff.
1490            my ($suffix, $mappedNameListRef, $mappedNameHashRef) =
1491                $self->_SetupSQL($objectNames, $filterClause, $matchClause);
1492            # Create the query. Note that the match clause is inserted at the front of
1493            # the select fields.
1494            my $command = "SELECT DISTINCT $matchClause, " . join(".*, ", @{$mappedNameListRef}) .
1495                ".* $suffix";
1496            my $sth = $self->_GetStatementHandle($command, \@myParams);
1497            # Now we create the relation map, which enables DBQuery to determine the order, name
1498            # and mapped name for each object in the query.
1499            my @relationMap = _RelationMap($mappedNameHashRef, $mappedNameListRef);
1500            # Return the statement object.
1501            $retVal = DBQuery::_new($self, $sth, \@relationMap, $object1Name);
1502        }
1503        return $retVal;
1504    }
1505    
1506    =head3 GetFlat
1507    
1508    C<< my @list = $erdb->GetFlat(\@objectNames, $filterClause, \@parameterList, $field); >>
1509    
1510    This is a variation of L</GetAll> that asks for only a single field per record and
1511    returns a single flattened list.
1512    
1513    =over 4
1514    
1515    =item objectNames
1516    
1517    List containing the names of the entity and relationship objects to be retrieved.
1518    
1519    =item filterClause
1520    
1521    WHERE/ORDER BY clause (without the WHERE) to be used to filter and sort the query. The WHERE clause can
1522    be parameterized with parameter markers (C<?>). Each field used must be specified in the standard form
1523    B<I<objectName>(I<fieldName>)>. Any parameters specified in the filter clause should be added to the
1524    parameter list as additional parameters. The fields in a filter clause can come from primary
1525    entity relations, relationship relations, or secondary entity relations; however, all of the
1526    entities and relationships involved must be included in the list of object names.
1527    
1528    =item parameterList
1529    
1530  =item param1, param2, ..., paramN  List of the parameters to be substituted in for the parameters marks in the filter clause.
1531    
1532  Parameter values to be substituted into the filter clause.  =item field
1533    
1534    Name of the field to be used to get the elements of the list returned.
1535    
1536  =item RETURN  =item RETURN
1537    
1538  Returns a list of B<DBObject>s that satisfy the query conditions.  Returns a list of values.
1539    
1540  =back  =back
1541    
1542  =cut  =cut
1543  #: Return Type @%  #: Return Type @;
1544  sub GetList {  sub GetFlat {
1545      # Get the parameters.      # Get the parameters.
1546      my ($self, $objectNames, $filterClause, @params) = @_;      my ($self, $objectNames, $filterClause, $parameterList, $field) = @_;
1547          # Declare the return variable.      # Construct the query.
1548        my $query = $self->Get($objectNames, $filterClause, $parameterList);
1549        # Create the result list.
1550          my @retVal = ();          my @retVal = ();
1551          # Perform the query.      # Loop through the records, adding the field values found to the result list.
1552          my $query = $self->Get($objectNames, $filterClause, @params);      while (my $row = $query->Fetch()) {
1553          # Loop through the results.          push @retVal, $row->Value($field);
         while (my $object = $query->Fetch) {  
                 push @retVal, $object;  
1554          }          }
1555      # Return the result.      # Return the list created.
1556      return @retVal;      return @retVal;
1557  }  }
1558    
1559  =head3 ComputeObjectSentence  =head3 SpecialFields
1560    
1561  C<< my $sentence = $database->ComputeObjectSentence($objectName); >>  C<< my %specials = $erdb->SpecialFields($entityName); >>
1562    
1563  Check an object name, and if it is a relationship convert it to a relationship sentence.  Return a hash mapping special fields in the specified entity to the value of their
1564    C<special> attribute. This enables the subclass to get access to the special field
1565    attributes without needed to plumb the internal ERDB data structures.
1566    
1567  =over 4  =over 4
1568    
1569  =item objectName  =item entityName
1570    
1571  Name of the entity or relationship.  Name of the entity whose special fields are desired.
1572    
1573  =item RETURN  =item RETURN
1574    
1575  Returns a string containing the entity name or a relationship sentence.  Returns a hash. The keys of the hash are the special field names, and the values
1576    are the values from each special field's C<special> attribute.
1577    
1578    =back
1579    
1580    =cut
1581    
1582    sub SpecialFields {
1583        # Get the parameters.
1584        my ($self, $entityName) = @_;
1585        # Declare the return variable.
1586        my %retVal = ();
1587        # Find the entity's data structure.
1588        my $entityData = $self->{_metaData}->{Entities}->{$entityName};
1589        # Loop through its fields, adding each special field to the return hash.
1590        my $fieldHash = $entityData->{Fields};
1591        for my $fieldName (keys %{$fieldHash}) {
1592            my $fieldData = $fieldHash->{$fieldName};
1593            if (exists $fieldData->{special}) {
1594                $retVal{$fieldName} = $fieldData->{special};
1595            }
1596        }
1597        # Return the result.
1598        return %retVal;
1599    }
1600    
1601    =head3 Delete
1602    
1603    C<< my $stats = $erdb->Delete($entityName, $objectID); >>
1604    
1605    Delete an entity instance from the database. The instance is deleted along with all entity and
1606    relationship instances dependent on it. The idea of dependence here is recursive. An object is
1607    always dependent on itself. An object is dependent if it is a 1-to-many or many-to-many
1608    relationship connected to a dependent entity or the "to" entity connected to a 1-to-many
1609    dependent relationship.
1610    
1611    =over 4
1612    
1613    =item entityName
1614    
1615    Name of the entity type for the instance being deleted.
1616    
1617    =item objectID
1618    
1619    ID of the entity instance to be deleted. If the ID contains a wild card character (C<%>),
1620    then it is presumed to by a LIKE pattern.
1621    
1622    =item testFlag
1623    
1624    If TRUE, the delete statements will be traced without being executed.
1625    
1626    =item RETURN
1627    
1628    Returns a statistics object indicating how many records of each particular table were
1629    deleted.
1630    
1631    =back
1632    
1633    =cut
1634    #: Return Type $%;
1635    sub Delete {
1636        # Get the parameters.
1637        my ($self, $entityName, $objectID, $testFlag) = @_;
1638        # Declare the return variable.
1639        my $retVal = Stats->new();
1640        # Get the DBKernel object.
1641        my $db = $self->{_dbh};
1642        # We're going to generate all the paths branching out from the starting entity. One of
1643        # the things we have to be careful about is preventing loops. We'll use a hash to
1644        # determine if we've hit a loop.
1645        my %alreadyFound = ();
1646        # These next lists will serve as our result stack. We start by pushing object lists onto
1647        # the stack, and then popping them off to do the deletes. This means the deletes will
1648        # start with the longer paths before getting to the shorter ones. That, in turn, makes
1649        # sure we don't delete records that might be needed to forge relationships back to the
1650        # original item. We have two lists-- one for TO-relationships, and one for
1651        # FROM-relationships and entities.
1652        my @fromPathList = ();
1653        my @toPathList = ();
1654        # This final hash is used to remember what work still needs to be done. We push paths
1655        # onto the list, then pop them off to extend the paths. We prime it with the starting
1656        # point. Note that we will work hard to insure that the last item on a path in the
1657        # to-do list is always an entity.
1658        my @todoList = ([$entityName]);
1659        while (@todoList) {
1660            # Get the current path.
1661            my $current = pop @todoList;
1662            # Copy it into a list.
1663            my @stackedPath = @{$current};
1664            # Pull off the last item on the path. It will always be an entity.
1665            my $entityName = pop @stackedPath;
1666            # Add it to the alreadyFound list.
1667            $alreadyFound{$entityName} = 1;
1668            # Get the entity data.
1669            my $entityData = $self->_GetStructure($entityName);
1670            # The first task is to loop through the entity's relation. A DELETE command will
1671            # be needed for each of them.
1672            my $relations = $entityData->{Relations};
1673            for my $relation (keys %{$relations}) {
1674                my @augmentedList = (@stackedPath, $relation);
1675                push @fromPathList, \@augmentedList;
1676            }
1677            # Now we need to look for relationships connected to this entity.
1678            my $relationshipList = $self->{_metaData}->{Relationships};
1679            for my $relationshipName (keys %{$relationshipList}) {
1680                my $relationship = $relationshipList->{$relationshipName};
1681                # Check the FROM field. We're only interested if it's us.
1682                if ($relationship->{from} eq $entityName) {
1683                    # Add the path to this relationship.
1684                    my @augmentedList = (@stackedPath, $entityName, $relationshipName);
1685                    push @fromPathList, \@augmentedList;
1686                    # Check the arity. If it's MM we're done. If it's 1M
1687                    # and the target hasn't been seen yet, we want to
1688                    # stack the entity for future processing.
1689                    if ($relationship->{arity} eq '1M') {
1690                        my $toEntity = $relationship->{to};
1691                        if (! exists $alreadyFound{$toEntity}) {
1692                            # Here we have a new entity that's dependent on
1693                            # the current entity, so we need to stack it.
1694                            my @stackList = (@augmentedList, $toEntity);
1695                            push @fromPathList, \@stackList;
1696                        } else {
1697                            Trace("$toEntity ignored because it occurred previously.") if T(4);
1698                        }
1699                    }
1700                }
1701                # Now check the TO field. In this case only the relationship needs
1702                # deletion.
1703                if ($relationship->{to} eq $entityName) {
1704                    my @augmentedList = (@stackedPath, $entityName, $relationshipName);
1705                    push @toPathList, \@augmentedList;
1706                }
1707            }
1708        }
1709        # Create the first qualifier for the WHERE clause. This selects the
1710        # keys of the primary entity records to be deleted. When we're deleting
1711        # from a dependent table, we construct a join page from the first qualifier
1712        # to the table containing the dependent records to delete.
1713        my $qualifier = ($objectID =~ /%/ ? "LIKE ?" : "= ?");
1714        # We need to make two passes. The first is through the to-list, and
1715        # the second through the from-list. The from-list is second because
1716        # the to-list may need to pass through some of the entities the
1717        # from-list would delete.
1718        my %stackList = ( from_link => \@fromPathList, to_link => \@toPathList );
1719        # Now it's time to do the deletes. We do it in two passes.
1720        for my $keyName ('to_link', 'from_link') {
1721            # Get the list for this key.
1722            my @pathList = @{$stackList{$keyName}};
1723            Trace(scalar(@pathList) . " entries in path list for $keyName.") if T(3);
1724            # Loop through this list.
1725            while (my $path = pop @pathList) {
1726                # Get the table whose rows are to be deleted.
1727                my @pathTables = @{$path};
1728                # Start the DELETE statement. We need to call DBKernel because the
1729                # syntax of a DELETE-USING varies among DBMSs.
1730                my $target = $pathTables[$#pathTables];
1731                my $stmt = $db->SetUsing(@pathTables);
1732                # Now start the WHERE. The first thing is the ID field from the starting table. That
1733                # starting table will either be the entity relation or one of the entity's
1734                # sub-relations.
1735                $stmt .= " WHERE $pathTables[0].id $qualifier";
1736                # Now we run through the remaining entities in the path, connecting them up.
1737                for (my $i = 1; $i <= $#pathTables; $i += 2) {
1738                    # Connect the current relationship to the preceding entity.
1739                    my ($entity, $rel) = @pathTables[$i-1,$i];
1740                    # The style of connection depends on the direction of the relationship.
1741                    $stmt .= " AND $entity.id = $rel.$keyName";
1742                    if ($i + 1 <= $#pathTables) {
1743                        # Here there's a next entity, so connect that to the relationship's
1744                        # to-link.
1745                        my $entity2 = $pathTables[$i+1];
1746                        $stmt .= " AND $rel.to_link = $entity2.id";
1747                    }
1748                }
1749                # Now we have our desired DELETE statement.
1750                if ($testFlag) {
1751                    # Here the user wants to trace without executing.
1752                    Trace($stmt) if T(0);
1753                } else {
1754                    # Here we can delete. Note that the SQL method dies with a confessing
1755                    # if an error occurs, so we just go ahead and do it.
1756                    Trace("Executing delete from $target using '$objectID'.") if T(3);
1757                    my $rv = $db->SQL($stmt, 0, $objectID);
1758                    # Accumulate the statistics for this delete. The only rows deleted
1759                    # are from the target table, so we use its name to record the
1760                    # statistic.
1761                    $retVal->Add($target, $rv);
1762                }
1763            }
1764        }
1765        # Return the result.
1766        return $retVal;
1767    }
1768    
1769    =head3 SortNeeded
1770    
1771    C<< my $parms = $erdb->SortNeeded($relationName); >>
1772    
1773    Return the pipe command for the sort that should be applied to the specified
1774    relation when creating the load file.
1775    
1776    For example, if the load file should be sorted ascending by the first
1777    field, this method would return
1778    
1779        sort -k1 -t"\t"
1780    
1781    If the first field is numeric, the method would return
1782    
1783        sort -k1n -t"\t"
1784    
1785    Unfortunately, due to a bug in the C<sort> command, we cannot eliminate duplicate
1786    keys using a sort.
1787    
1788    =over 4
1789    
1790    =item relationName
1791    
1792    Name of the relation to be examined.
1793    
1794    =item
1795    
1796    Returns the sort command to use for sorting the relation, suitable for piping.
1797    
1798    =back
1799    
1800    =cut
1801    #: Return Type $;
1802    sub SortNeeded {
1803        # Get the parameters.
1804        my ($self, $relationName) = @_;
1805        # Declare a descriptor to hold the names of the key fields.
1806        my @keyNames = ();
1807        # Get the relation structure.
1808        my $relationData = $self->_FindRelation($relationName);
1809        # Find out if the relation is a primary entity relation,
1810        # a relationship relation, or a secondary entity relation.
1811        my $entityTable = $self->{_metaData}->{Entities};
1812        my $relationshipTable = $self->{_metaData}->{Relationships};
1813        if (exists $entityTable->{$relationName}) {
1814            # Here we have a primary entity relation.
1815            push @keyNames, "id";
1816        } elsif (exists $relationshipTable->{$relationName}) {
1817            # Here we have a relationship. We sort using the FROM index.
1818            my $relationshipData = $relationshipTable->{$relationName};
1819            my $index = $relationData->{Indexes}->{idxFrom};
1820            push @keyNames, @{$index->{IndexFields}};
1821        } else {
1822            # Here we have a secondary entity relation, so we have a sort on the ID field.
1823            push @keyNames, "id";
1824        }
1825        # Now we parse the key names into sort parameters. First, we prime the return
1826        # string.
1827        my $retVal = "sort -t\"\t\" ";
1828        # Get the relation's field list.
1829        my @fields = @{$relationData->{Fields}};
1830        # Loop through the keys.
1831        for my $keyData (@keyNames) {
1832            # Get the key and the ordering.
1833            my ($keyName, $ordering);
1834            if ($keyData =~ /^([^ ]+) DESC/) {
1835                ($keyName, $ordering) = ($1, "descending");
1836            } else {
1837                ($keyName, $ordering) = ($keyData, "ascending");
1838            }
1839            # Find the key's position and type.
1840            my $fieldSpec;
1841            for (my $i = 0; $i <= $#fields && ! $fieldSpec; $i++) {
1842                my $thisField = $fields[$i];
1843                if ($thisField->{name} eq $keyName) {
1844                    # Get the sort modifier for this field type. The modifier
1845                    # decides whether we're using a character, numeric, or
1846                    # floating-point sort.
1847                    my $modifier = $TypeTable{$thisField->{type}}->{sort};
1848                    # If the index is descending for this field, denote we want
1849                    # to reverse the sort order on this field.
1850                    if ($ordering eq 'descending') {
1851                        $modifier .= "r";
1852                    }
1853                    # Store the position and modifier into the field spec, which
1854                    # will stop the inner loop. Note that the field number is
1855                    # 1-based in the sort command, so we have to increment the
1856                    # index.
1857                    $fieldSpec = ($i + 1) . $modifier;
1858                }
1859            }
1860            # Add this field to the sort command.
1861            $retVal .= " -k$fieldSpec";
1862        }
1863        # Return the result.
1864        return $retVal;
1865    }
1866    
1867    =head3 GetList
1868    
1869    C<< my @dbObjects = $erdb->GetList(\@objectNames, $filterClause, \@params); >>
1870    
1871    Return a list of object descriptors for the specified objects as determined by the
1872    specified filter clause.
1873    
1874    This method is essentially the same as L</Get> except it returns a list of objects rather
1875    than a query object that can be used to get the results one record at a time.
1876    
1877    =over 4
1878    
1879    =item objectNames
1880    
1881    List containing the names of the entity and relationship objects to be retrieved.
1882    
1883    =item filterClause
1884    
1885    WHERE clause (without the WHERE) to be used to filter and sort the query. The WHERE clause can
1886    be parameterized with parameter markers (C<?>). Each field used in the WHERE clause must be
1887    specified in the standard form B<I<objectName>(I<fieldName>)>. Any parameters specified
1888    in the filter clause should be added to the parameter list as additional parameters. The
1889    fields in a filter clause can come from primary entity relations, relationship relations,
1890    or secondary entity relations; however, all of the entities and relationships involved must
1891    be included in the list of object names.
1892    
1893    The filter clause can also specify a sort order. To do this, simply follow the filter string
1894    with an ORDER BY clause. For example, the following filter string gets all genomes for a
1895    particular genus and sorts them by species name.
1896    
1897    C<< "Genome(genus) = ? ORDER BY Genome(species)" >>
1898    
1899    The rules for field references in a sort order are the same as those for field references in the
1900    filter clause in general; however, odd things may happen if a sort field is from a secondary
1901    relation.
1902    
1903    =item params
1904    
1905    Reference to a list of parameter values to be substituted into the filter clause.
1906    
1907    =item RETURN
1908    
1909    Returns a list of B<DBObject>s that satisfy the query conditions.
1910    
1911    =back
1912    
1913    =cut
1914    #: Return Type @%
1915    sub GetList {
1916        # Get the parameters.
1917        my ($self, $objectNames, $filterClause, $params) = @_;
1918        # Declare the return variable.
1919        my @retVal = ();
1920        # Perform the query.
1921        my $query = $self->Get($objectNames, $filterClause, $params);
1922        # Loop through the results.
1923        while (my $object = $query->Fetch) {
1924            push @retVal, $object;
1925        }
1926        # Return the result.
1927        return @retVal;
1928    }
1929    
1930    =head3 GetCount
1931    
1932    C<< my $count = $erdb->GetCount(\@objectNames, $filter, \@params); >>
1933    
1934    Return the number of rows found by a specified query. This method would
1935    normally be used to count the records in a single table. For example, in a
1936    genetics database
1937    
1938        my $count = $erdb->GetCount(['Genome'], 'Genome(genus-species) LIKE ?', ['homo %']);
1939    
1940    would return the number of genomes for the genus I<homo>. It is conceivable, however,
1941    to use it to return records based on a join. For example,
1942    
1943        my $count = $erdb->GetCount(['HasFeature', 'Genome'], 'Genome(genus-species) LIKE ?',
1944                                    ['homo %']);
1945    
1946    would return the number of features for genomes in the genus I<homo>. Note that
1947    only the rows from the first table are counted. If the above command were
1948    
1949        my $count = $erdb->GetCount(['Genome', 'Feature'], 'Genome(genus-species) LIKE ?',
1950                                    ['homo %']);
1951    
1952    it would return the number of genomes, not the number of genome/feature pairs.
1953    
1954    =over 4
1955    
1956    =item objectNames
1957    
1958    Reference to a list of the objects (entities and relationships) included in the
1959    query.
1960    
1961    =item filter
1962    
1963    A filter clause for restricting the query. The rules are the same as for the L</Get>
1964    method.
1965    
1966    =item params
1967    
1968    Reference to a list of the parameter values to be substituted for the parameter marks
1969    in the filter.
1970    
1971    =item RETURN
1972    
1973    Returns a count of the number of records in the first table that would satisfy
1974    the query.
1975    
1976    =back
1977    
1978    =cut
1979    
1980    sub GetCount {
1981        # Get the parameters.
1982        my ($self, $objectNames, $filter, $params) = @_;
1983        # Insure the params argument is an array reference if the caller left it off.
1984        if (! defined($params)) {
1985            $params = [];
1986        }
1987        # Declare the return variable.
1988        my $retVal;
1989        # Find out if we're counting an entity or a relationship.
1990        my $countedField;
1991        if ($self->IsEntity($objectNames->[0])) {
1992            $countedField = "id";
1993        } else {
1994            # For a relationship we count the to-link because it's usually more
1995            # numerous. Note we're automatically converting to the SQL form
1996            # of the field name (to_link vs. to-link).
1997            $countedField = "to_link";
1998        }
1999        # Create the SQL command suffix to get the desired records.
2000        my ($suffix, $mappedNameListRef, $mappedNameHashRef) = $self->_SetupSQL($objectNames,
2001                                                                                $filter);
2002        # Prefix it with text telling it we want a record count.
2003        my $firstObject = $mappedNameListRef->[0];
2004        my $command = "SELECT COUNT($firstObject.$countedField) $suffix";
2005        # Prepare and execute the command.
2006        my $sth = $self->_GetStatementHandle($command, $params);
2007        # Get the count value.
2008        ($retVal) = $sth->fetchrow_array();
2009        # Check for a problem.
2010        if (! defined($retVal)) {
2011            if ($sth->err) {
2012                # Here we had an SQL error.
2013                Confess("Error retrieving row count: " . $sth->errstr());
2014            } else {
2015                # Here we have no result.
2016                Confess("No result attempting to retrieve row count.");
2017            }
2018        }
2019        # Return the result.
2020        return $retVal;
2021    }
2022    
2023    =head3 ComputeObjectSentence
2024    
2025    C<< my $sentence = $erdb->ComputeObjectSentence($objectName); >>
2026    
2027    Check an object name, and if it is a relationship convert it to a relationship sentence.
2028    
2029    =over 4
2030    
2031    =item objectName
2032    
2033    Name of the entity or relationship.
2034    
2035    =item RETURN
2036    
2037    Returns a string containing the entity name or a relationship sentence.
2038    
2039  =back  =back
2040    
# Line 847  Line 2057 
2057    
2058  =head3 DumpRelations  =head3 DumpRelations
2059    
2060  C<< $database->DumpRelations($outputDirectory); >>  C<< $erdb->DumpRelations($outputDirectory); >>
2061    
2062  Write the contents of all the relations to tab-delimited files in the specified directory.  Write the contents of all the relations to tab-delimited files in the specified directory.
2063  Each file will have the same name as the relation dumped, with an extension of DTX.  Each file will have the same name as the relation dumped, with an extension of DTX.
# Line 887  Line 2097 
2097          }          }
2098  }  }
2099    
2100    =head3 InsertValue
2101    
2102    C<< $erdb->InsertValue($entityID, $fieldName, $value); >>
2103    
2104    This method will insert a new value into the database. The value must be one
2105    associated with a secondary relation, since primary values cannot be inserted:
2106    they occur exactly once. Secondary values, on the other hand, can be missing
2107    or multiply-occurring.
2108    
2109    =over 4
2110    
2111    =item entityID
2112    
2113    ID of the object that is to receive the new value.
2114    
2115    =item fieldName
2116    
2117    Field name for the new value-- this includes the entity name, since
2118    field names are of the format I<objectName>C<(>I<fieldName>C<)>.
2119    
2120    =item value
2121    
2122    New value to be put in the field.
2123    
2124    =back
2125    
2126    =cut
2127    
2128    sub InsertValue {
2129        # Get the parameters.
2130        my ($self, $entityID, $fieldName, $value) = @_;
2131        # Parse the entity name and the real field name.
2132        if ($fieldName =~ /^([^(]+)\(([^)]+)\)/) {
2133            my $entityName = $1;
2134            my $fieldTitle = $2;
2135            # Get its descriptor.
2136            if (!$self->IsEntity($entityName)) {
2137                Confess("$entityName is not a valid entity.");
2138            } else {
2139                my $entityData = $self->{_metaData}->{Entities}->{$entityName};
2140                # Find the relation containing this field.
2141                my $fieldHash = $entityData->{Fields};
2142                if (! exists $fieldHash->{$fieldTitle}) {
2143                    Confess("$fieldTitle not found in $entityName.");
2144                } else {
2145                    my $relation = $fieldHash->{$fieldTitle}->{relation};
2146                    if ($relation eq $entityName) {
2147                        Confess("Cannot do InsertValue on primary field $fieldTitle of $entityName.");
2148                    } else {
2149                        # Now we can create an INSERT statement.
2150                        my $dbh = $self->{_dbh};
2151                        my $fixedName = _FixName($fieldTitle);
2152                        my $statement = "INSERT INTO $relation (id, $fixedName) VALUES(?, ?)";
2153                        # Execute the command.
2154                        $dbh->SQL($statement, 0, $entityID, $value);
2155                    }
2156                }
2157            }
2158        } else {
2159            Confess("$fieldName is not a valid field name.");
2160        }
2161    }
2162    
2163  =head3 InsertObject  =head3 InsertObject
2164    
2165  C<< my $ok = $database->InsertObject($objectType, \%fieldHash); >>  C<< my $ok = $erdb->InsertObject($objectType, \%fieldHash); >>
2166    
2167  Insert an object into the database. The object is defined by a type name and then a hash  Insert an object into the database. The object is defined by a type name and then a hash
2168  of field names to values. Field values in the primary relation are represented by scalars.  of field names to values. Field values in the primary relation are represented by scalars.
# Line 898  Line 2171 
2171  example, the following line inserts an inactive PEG feature named C<fig|188.1.peg.1> with aliases  example, the following line inserts an inactive PEG feature named C<fig|188.1.peg.1> with aliases
2172  C<ZP_00210270.1> and C<gi|46206278>.  C<ZP_00210270.1> and C<gi|46206278>.
2173    
2174  C<< $database->InsertObject('Feature', { id => 'fig|188.1.peg.1', active => 0, feature-type => 'peg', alias => ['ZP_00210270.1', 'gi|46206278']}); >>  C<< $erdb->InsertObject('Feature', { id => 'fig|188.1.peg.1', active => 0, feature-type => 'peg', alias => ['ZP_00210270.1', 'gi|46206278']}); >>
2175    
2176  The next statement inserts a C<HasProperty> relationship between feature C<fig|158879.1.peg.1> and  The next statement inserts a C<HasProperty> relationship between feature C<fig|158879.1.peg.1> and
2177  property C<4> with an evidence URL of C<http://seedu.uchicago.edu/query.cgi?article_id=142>.  property C<4> with an evidence URL of C<http://seedu.uchicago.edu/query.cgi?article_id=142>.
2178    
2179  C<< $database->InsertObject('HasProperty', { 'from-link' => 'fig|158879.1.peg.1', 'to-link' => 4, evidence = 'http://seedu.uchicago.edu/query.cgi?article_id=142'}); >>  C<< $erdb->InsertObject('HasProperty', { 'from-link' => 'fig|158879.1.peg.1', 'to-link' => 4, evidence => 'http://seedu.uchicago.edu/query.cgi?article_id=142'}); >>
2180    
2181  =over 4  =over 4
2182    
# Line 1028  Line 2301 
2301    
2302  =head3 LoadTable  =head3 LoadTable
2303    
2304  C<< my %results = $database->LoadTable($fileName, $relationName, $truncateFlag); >>  C<< my %results = $erdb->LoadTable($fileName, $relationName, $truncateFlag); >>
2305    
2306  Load data from a tab-delimited file into a specified table, optionally re-creating the table first.  Load data from a tab-delimited file into a specified table, optionally re-creating the table
2307    first.
2308    
2309  =over 4  =over 4
2310    
# Line 1048  Line 2322 
2322    
2323  =item RETURN  =item RETURN
2324    
2325  Returns a statistical object containing the number of records read and a list of the error messages.  Returns a statistical object containing a list of the error messages.
2326    
2327  =back  =back
2328    
# Line 1059  Line 2333 
2333          # Create the statistical return object.          # Create the statistical return object.
2334          my $retVal = _GetLoadStats();          my $retVal = _GetLoadStats();
2335          # Trace the fact of the load.          # Trace the fact of the load.
2336          Trace("Loading table $relationName from $fileName") if T(1);      Trace("Loading table $relationName from $fileName") if T(2);
2337          # Get the database handle.          # Get the database handle.
2338          my $dbh = $self->{_dbh};          my $dbh = $self->{_dbh};
2339        # Get the input file size.
2340        my $fileSize = -s $fileName;
2341          # Get the relation data.          # Get the relation data.
2342          my $relation = $self->_FindRelation($relationName);          my $relation = $self->_FindRelation($relationName);
2343          # Check the truncation flag.          # Check the truncation flag.
2344          if ($truncateFlag) {          if ($truncateFlag) {
2345                  Trace("Creating table $relationName") if T(1);          Trace("Creating table $relationName") if T(2);
2346            # Compute the row count estimate. We take the size of the load file,
2347            # divide it by the estimated row size, and then multiply by 1.5 to
2348            # leave extra room. We postulate a minimum row count of 1000 to
2349            # prevent problems with incoming empty load files.
2350            my $rowSize = $self->EstimateRowSize($relationName);
2351            my $estimate = FIG::max($fileSize * 1.5 / $rowSize, 1000);
2352                  # Re-create the table without its index.                  # Re-create the table without its index.
2353                  $self->CreateTable($relationName, 0);          $self->CreateTable($relationName, 0, $estimate);
2354            # If this is a pre-index DBMS, create the index here.
2355            if ($dbh->{_preIndex}) {
2356                eval {
2357                    $self->CreateIndex($relationName);
2358                };
2359                if ($@) {
2360                    $retVal->AddMessage($@);
2361                }
2362            }
2363          }          }
         # Determine whether or not this is a primary relation. Primary relations have an extra  
         # field indicating whether or not a given object is new or was loaded from the flat files.  
         my $primary = $self->_IsPrimary($relationName);  
         # Get the number of fields in this relation.  
         my @fieldList = @{$relation->{Fields}};  
         my $fieldCount = @fieldList;  
         # Record the number of expected fields.  
         my $expectedFields = $fieldCount + ($primary ? 1 : 0);  
         # Start a database transaction.  
         $dbh->begin_tran;  
         # Open the relation file. We need to create a cleaned-up copy before loading.  
         open TABLEIN, '<', $fileName;  
         my $tempName = "$fileName.tbl";  
         open TABLEOUT, '>', $tempName;  
         # Loop through the file.  
         while (<TABLEIN>) {  
                 # Chop off the new-line character.  
                 my $record = $_;  
                 chomp $record;  
         # Only proceed if the record is non-blank.  
         if ($record) {  
             # Escape all the backslashes found in the line.  
             $record =~ s/\\/\\\\/g;  
             # Eliminate any trailing tabs.  
             chop $record while substr($record, -1) eq "\t";  
             # If this is a primary relation, add a 0 for the new-record flag (indicating that  
             # this record is not new, but part of the original load).  
             if ($primary) {  
                 $record .= "\t0";  
             }  
             # Write the record.  
             print TABLEOUT "$record\n";  
             # Count the record read.  
             my $count = $retVal->Add('records');  
             my $len = length $record;  
             Trace("Record $count written with $len characters.") if T(4);  
         }  
         }  
         # Close the files.  
         close TABLEIN;  
         close TABLEOUT;  
     Trace("Temporary file $tempName created.") if T(4);  
2364      # Load the table.      # Load the table.
2365          my $rv;          my $rv;
2366          eval {          eval {
2367                  $rv = $dbh->load_table(file => $tempName, tbl => $relationName);          $rv = $dbh->load_table(file => $fileName, tbl => $relationName);
2368          };          };
2369          if (!defined $rv) {          if (!defined $rv) {
2370          $retVal->AddMessage($@) if ($@);          $retVal->AddMessage($@) if ($@);
2371          $retVal->AddMessage("Table load failed for $relationName using $tempName.");          $retVal->AddMessage("Table load failed for $relationName using $fileName: " . $dbh->error_message);
2372                  Trace("Table load failed for $relationName.") if T(1);                  Trace("Table load failed for $relationName.") if T(1);
2373          } else {          } else {
2374                  # Here we successfully loaded the table. Trace the number of records loaded.          # Here we successfully loaded the table.
2375                  Trace("$retVal->{records} records read for $relationName.") if T(1);          $retVal->Add("tables");
2376            my $size = -s $fileName;
2377            Trace("$size bytes loaded into $relationName.") if T(2);
2378                  # If we're rebuilding, we need to create the table indexes.                  # If we're rebuilding, we need to create the table indexes.
2379                  if ($truncateFlag) {                  if ($truncateFlag) {
2380                # Indexes are created here for PostGres. For PostGres, indexes are
2381                # best built at the end. For MySQL, the reverse is true.
2382                if (! $dbh->{_preIndex}) {
2383                          eval {                          eval {
2384                                  $self->CreateIndex($relationName);                                  $self->CreateIndex($relationName);
2385                          };                          };
# Line 1133  Line 2387 
2387                                  $retVal->AddMessage($@);                                  $retVal->AddMessage($@);
2388                          }                          }
2389                  }                  }
2390                # The full-text index (if any) is always built last, even for MySQL.
2391                # First we need to see if this table has a full-text index. Only
2392                # primary relations are allowed that privilege.
2393                if ($self->_IsPrimary($relationName)) {
2394                    # Get the relation's entity/relationship structure.
2395                    my $structure = $self->_GetStructure($relationName);
2396                    # Check for a searchable fields list.
2397                    if (exists $structure->{searchFields}) {
2398                        # Here we know that we need to create a full-text search index.
2399                        # Get an SQL-formatted field name list.
2400                        my $fields = join(", ", $self->_FixNames(@{$structure->{searchFields}}));
2401                        # Create the index.
2402                        $dbh->create_index(tbl => $relationName, idx => "search_idx",
2403                                           flds => $fields, kind => 'fulltext');
2404                    }
2405                }
2406            }
2407          }          }
2408          # Commit the database changes.      # Analyze the table to improve performance.
2409          $dbh->commit_tran;      Trace("Analyzing and compacting $relationName.") if T(3);
2410          # Delete the temporary file.      $dbh->vacuum_it($relationName);
2411          unlink $tempName;      Trace("$relationName load completed.") if T(3);
2412          # Return the statistics.          # Return the statistics.
2413          return $retVal;          return $retVal;
2414  }  }
2415    
2416  =head3 GenerateEntity  =head3 DropRelation
2417    
2418  C<< my $fieldHash = $database->GenerateEntity($id, $type, \%values); >>  C<< $erdb->DropRelation($relationName); >>
2419    
2420  Generate the data for a new entity instance. This method creates a field hash suitable for  Physically drop a relation from the database.
 passing as a parameter to L</InsertObject>. The ID is specified by the callr, but the rest  
 of the fields are generated using information in the database schema.  
   
 Each data type has a default algorithm for generating random test data. This can be overridden  
 by including a B<DataGen> element in the field. If this happens, the content of the element is  
 executed as a PERL program in the context of this module. The element may make use of a C<$this>  
 variable which contains the field hash as it has been built up to the current point. If any  
 fields are dependent on other fields, the C<pass> attribute can be used to control the order  
 in which the fields are generated. A field with a high data pass number will be generated after  
 a field with a lower one. If any external values are needed, they should be passed in via the  
 optional third parameter, which will be available to the data generation script under the name  
 C<$value>. Several useful utility methods are provided for generating random values, including  
 L</IntGen>, L</StringGen>, L</FloatGen>, and L</DateGen>. Note that dates are stored and generated  
 in the form of a timestamp number rather than a string.  
2421    
2422  =over 4  =over 4
2423    
2424  =item id  =item relationName
   
 ID to assign to the new entity.  
   
 =item type  
   
 Type name for the new entity.  
   
 =item values  
2425    
2426  Hash containing additional values that might be needed by the data generation methods (optional).  Name of the relation to drop. If it does not exist, this method will have
2427    no effect.
2428    
2429  =back  =back
2430    
2431  =cut  =cut
2432    
2433  sub GenerateEntity {  sub DropRelation {
2434          # Get the parameters.          # Get the parameters.
2435          my ($self, $id, $type, $values) = @_;      my ($self, $relationName) = @_;
2436          # Create the return hash.      # Get the database handle.
2437          my $this = { id => $id };      my $dbh = $self->{_dbh};
2438          # Get the metadata structure.      # Drop the relation. The method used here has no effect if the relation
2439          my $metadata = $self->{_metaData};      # does not exist.
2440          # Get this entity's list of fields.      Trace("Invoking DB Kernel to drop $relationName.") if T(3);
2441          if (!exists $metadata->{Entities}->{$type}) {      $dbh->drop_table(tbl => $relationName);
                 Confess("Unrecognized entity type $type in GenerateEntity.");  
         } else {  
                 my $entity = $metadata->{Entities}->{$type};  
                 my $fields = $entity->{Fields};  
                 # Generate data from the fields.  
                 _GenerateFields($this, $fields, $type, $values);  
         }  
         # Return the hash created.  
         return $this;  
2442  }  }
2443    
2444  =head3 GetEntity  =head3 GetEntity
2445    
2446  C<< my $entityObject = $sprout->GetEntity($entityType, $ID); >>  C<< my $entityObject = $erdb->GetEntity($entityType, $ID); >>
2447    
2448  Return an object describing the entity instance with a specified ID.  Return an object describing the entity instance with a specified ID.
2449    
# Line 1229  Line 2470 
2470          # Get the parameters.          # Get the parameters.
2471          my ($self, $entityType, $ID) = @_;          my ($self, $entityType, $ID) = @_;
2472          # Create a query.          # Create a query.
2473          my $query = $self->Get([$entityType], "$entityType(id) = ?", $ID);      my $query = $self->Get([$entityType], "$entityType(id) = ?", [$ID]);
2474          # Get the first (and only) object.          # Get the first (and only) object.
2475          my $retVal = $query->Fetch();          my $retVal = $query->Fetch();
2476          # Return the result.          # Return the result.
2477          return $retVal;          return $retVal;
2478  }  }
2479    
2480  =head3 GetEntityValues  =head3 GetChoices
2481    
2482    C<< my @values = $erdb->GetChoices($entityName, $fieldName); >>
2483    
2484  C<< my @values = GetEntityValues($entityType, $ID, \@fields); >>  Return a list of all the values for the specified field that are represented in the
2485    specified entity.
2486    
2487  Return a list of values from a specified entity instance.  Note that if the field is not indexed, then this will be a very slow operation.
2488    
2489  =over 4  =over 4
2490    
2491  =item entityType  =item entityName
2492    
2493  Entity type name.  Name of an entity in the database.
2494    
2495  =item ID  =item fieldName
2496    
2497  ID of the desired entity.  Name of a field belonging to the entity. This is a raw field name without
2498    the standard parenthesized notation used in most calls.
2499    
2500  =item fields  =item RETURN
2501    
2502    Returns a list of the distinct values for the specified field in the database.
2503    
2504    =back
2505    
2506    =cut
2507    
2508    sub GetChoices {
2509        # Get the parameters.
2510        my ($self, $entityName, $fieldName) = @_;
2511        # Declare the return variable.
2512        my @retVal;
2513        # Get the entity data structure.
2514        my $entityData = $self->_GetStructure($entityName);
2515        # Get the field.
2516        my $fieldHash = $entityData->{Fields};
2517        if (! exists $fieldHash->{$fieldName}) {
2518            Confess("$fieldName not found in $entityName.");
2519        } else {
2520            # Get the name of the relation containing the field.
2521            my $relation = $fieldHash->{$fieldName}->{relation};
2522            # Fix up the field name.
2523            my $realName = _FixName($fieldName);
2524            # Get the database handle.
2525            my $dbh = $self->{_dbh};
2526            # Query the database.
2527            my $results = $dbh->SQL("SELECT DISTINCT $realName FROM $relation");
2528            # Clean the results. They are stored as a list of lists, and we just want the one list.
2529            @retVal = sort map { $_->[0] } @{$results};
2530        }
2531        # Return the result.
2532        return @retVal;
2533    }
2534    
2535    =head3 GetEntityValues
2536    
2537    C<< my @values = $erdb->GetEntityValues($entityType, $ID, \@fields); >>
2538    
2539    Return a list of values from a specified entity instance. If the entity instance
2540    does not exist, an empty list is returned.
2541    
2542    =over 4
2543    
2544    =item entityType
2545    
2546    Entity type name.
2547    
2548    =item ID
2549    
2550    ID of the desired entity.
2551    
2552    =item fields
2553    
2554  List of field names, each of the form I<objectName>C<(>I<fieldName>C<)>.  List of field names, each of the form I<objectName>C<(>I<fieldName>C<)>.
2555    
# Line 1279  Line 2576 
2576          return @retVal;          return @retVal;
2577  }  }
2578    
2579  =head2 Internal Utility Methods  =head3 GetAll
2580    
2581  =head3 GetLoadStats  C<< my @list = $erdb->GetAll(\@objectNames, $filterClause, \@parameters, \@fields, $count); >>
2582    
2583  Return a blank statistics object for use by the load methods.  Return a list of values taken from the objects returned by a query. The first three
2584    parameters correspond to the parameters of the L</Get> method. The final parameter is
2585    a list of the fields desired from each record found by the query. The field name
2586    syntax is the standard syntax used for fields in the B<ERDB> system--
2587    B<I<objectName>(I<fieldName>)>-- where I<objectName> is the name of the relevant entity
2588    or relationship and I<fieldName> is the name of the field.
2589    
2590    The list returned will be a list of lists. Each element of the list will contain
2591    the values returned for the fields specified in the fourth parameter. If one of the
2592    fields specified returns multiple values, they are flattened in with the rest. For
2593    example, the following call will return a list of the features in a particular
2594    spreadsheet cell, and each feature will be represented by a list containing the
2595    feature ID followed by all of its aliases.
2596    
2597  This is a static method.  C<< $query = $erdb->Get(['ContainsFeature', 'Feature'], "ContainsFeature(from-link) = ?", [$ssCellID], ['Feature(id)', 'Feature(alias)']); >>
2598    
2599    =over 4
2600    
2601    =item objectNames
2602    
2603    List containing the names of the entity and relationship objects to be retrieved.
2604    
2605    =item filterClause
2606    
2607    WHERE/ORDER BY clause (without the WHERE) to be used to filter and sort the query. The WHERE clause can
2608    be parameterized with parameter markers (C<?>). Each field used must be specified in the standard form
2609    B<I<objectName>(I<fieldName>)>. Any parameters specified in the filter clause should be added to the
2610    parameter list as additional parameters. The fields in a filter clause can come from primary
2611    entity relations, relationship relations, or secondary entity relations; however, all of the
2612    entities and relationships involved must be included in the list of object names.
2613    
2614    =item parameterList
2615    
2616    List of the parameters to be substituted in for the parameters marks in the filter clause.
2617    
2618    =item fields
2619    
2620    List of the fields to be returned in each element of the list returned.
2621    
2622    =item count
2623    
2624    Maximum number of records to return. If omitted or 0, all available records will be returned.
2625    
2626    =item RETURN
2627    
2628    Returns a list of list references. Each element of the return list contains the values for the
2629    fields specified in the B<fields> parameter.
2630    
2631    =back
2632    
2633  =cut  =cut
2634    #: Return Type @@;
2635    sub GetAll {
2636        # Get the parameters.
2637        my ($self, $objectNames, $filterClause, $parameterList, $fields, $count) = @_;
2638        # Translate the parameters from a list reference to a list. If the parameter
2639        # list is a scalar we convert it into a singleton list.
2640        my @parmList = ();
2641        if (ref $parameterList eq "ARRAY") {
2642            Trace("GetAll parm list is an array.") if T(4);
2643            @parmList = @{$parameterList};
2644        } else {
2645            Trace("GetAll parm list is a scalar: $parameterList.") if T(4);
2646            push @parmList, $parameterList;
2647        }
2648        # Insure the counter has a value.
2649        if (!defined $count) {
2650            $count = 0;
2651        }
2652        # Add the row limit to the filter clause.
2653        if ($count > 0) {
2654            $filterClause .= " LIMIT $count";
2655        }
2656        # Create the query.
2657        my $query = $self->Get($objectNames, $filterClause, \@parmList);
2658        # Set up a counter of the number of records read.
2659        my $fetched = 0;
2660        # Loop through the records returned, extracting the fields. Note that if the
2661        # counter is non-zero, we stop when the number of records read hits the count.
2662        my @retVal = ();
2663        while (($count == 0 || $fetched < $count) && (my $row = $query->Fetch())) {
2664            my @rowData = $row->Values($fields);
2665            push @retVal, \@rowData;
2666            $fetched++;
2667        }
2668        Trace("$fetched rows returned in GetAll.") if T(SQL => 4);
2669        # Return the resulting list.
2670        return @retVal;
2671    }
2672    
2673  sub _GetLoadStats {  =head3 Exists
2674          return Stats->new('records');  
2675    C<< my $found = $sprout->Exists($entityName, $entityID); >>
2676    
2677    Return TRUE if an entity exists, else FALSE.
2678    
2679    =over 4
2680    
2681    =item entityName
2682    
2683    Name of the entity type (e.g. C<Feature>) relevant to the existence check.
2684    
2685    =item entityID
2686    
2687    ID of the entity instance whose existence is to be checked.
2688    
2689    =item RETURN
2690    
2691    Returns TRUE if the entity instance exists, else FALSE.
2692    
2693    =back
2694    
2695    =cut
2696    #: Return Type $;
2697    sub Exists {
2698        # Get the parameters.
2699        my ($self, $entityName, $entityID) = @_;
2700        # Check for the entity instance.
2701        Trace("Checking existence of $entityName with ID=$entityID.") if T(4);
2702        my $testInstance = $self->GetEntity($entityName, $entityID);
2703        # Return an existence indicator.
2704        my $retVal = ($testInstance ? 1 : 0);
2705        return $retVal;
2706  }  }
2707    
2708  =head3 GenerateFields  =head3 EstimateRowSize
2709    
2710  Generate field values from a field structure and store in a specified table. The field names  C<< my $rowSize = $erdb->EstimateRowSize($relName); >>
 are first sorted by pass count, certain pre-defined fields are removed from the list, and  
 then we rip through them evaluation the data generation string. Fields in the primary relation  
 are stored as scalars; fields in secondary relations are stored as value lists.  
2711    
2712  This is a static method.  Estimate the row size of the specified relation. The estimated row size is computed by adding
2713    up the average length for each data type.
2714    
2715  =over 4  =over 4
2716    
2717  =item this  =item relName
2718    
2719  Hash table into which the field values should be placed.  Name of the relation whose estimated row size is desired.
2720    
2721  =item fields  =item RETURN
2722    
2723  Field structure from which the field descriptors should be taken.  Returns an estimate of the row size for the specified relation.
2724    
2725  =item type  =back
2726    
2727  Type name of the object whose fields are being generated.  =cut
2728    #: Return Type $;
2729    sub EstimateRowSize {
2730        # Get the parameters.
2731        my ($self, $relName) = @_;
2732        # Declare the return variable.
2733        my $retVal = 0;
2734        # Find the relation descriptor.
2735        my $relation = $self->_FindRelation($relName);
2736        # Get the list of fields.
2737        for my $fieldData (@{$relation->{Fields}}) {
2738            # Get the field type and add its length.
2739            my $fieldLen = $TypeTable{$fieldData->{type}}->{avgLen};
2740            $retVal += $fieldLen;
2741        }
2742        # Return the result.
2743        return $retVal;
2744    }
2745    
2746  =item values (optional)  =head3 GetFieldTable
2747    
2748  Reference to a value structure from which additional values can be taken.  C<< my $fieldHash = $self->GetFieldTable($objectnName); >>
2749    
2750  =item from (optiona)  Get the field structure for a specified entity or relationship.
2751    
2752  Reference to the source entity instance if relationship data is being generated.  =over 4
2753    
2754    =item objectName
2755    
2756    Name of the desired entity or relationship.
2757    
2758  =item to (optional)  =item RETURN
2759    
2760  Reference to the target entity instance if relationship data is being generated.  The table containing the field descriptors for the specified object.
2761    
2762  =back  =back
2763    
2764  =cut  =cut
2765    
2766  sub _GenerateFields {  sub GetFieldTable {
2767          # Get the parameters.          # Get the parameters.
2768          my ($this, $fields, $type, $values, $from, $to) = @_;      my ($self, $objectName) = @_;
2769          # Sort the field names by pass number.      # Get the descriptor from the metadata.
2770          my @fieldNames = sort { $fields->{$a}->{DataGen}->{pass} <=> $fields->{$b}->{DataGen}->{pass} } keys %{$fields};      my $objectData = $self->_GetStructure($objectName);
2771          # Loop through the field names, generating data.      # Return the object's field table.
2772          for my $name (@fieldNames) {      return $objectData->{Fields};
2773                  # Only proceed if this field needs to be generated.  }
2774                  if (!exists $this->{$name}) {  
2775                          # Get this field's data generation descriptor.  =head3 SplitKeywords
2776                          my $fieldDescriptor = $fields->{$name};  
2777                          my $data = $fieldDescriptor->{DataGen};  C<< my @keywords = ERDB::SplitKeywords($keywordString); >>
2778                          # Get the code to generate the field value.  
2779                          my $codeString = $data->{content};  This method returns a list of the positive keywords in the specified
2780                          # Determine whether or not this field is in the primary relation.  keyword string. All of the operators will have been stripped off,
2781                          if ($fieldDescriptor->{relation} eq $type) {  and if the keyword is preceded by a minus operator (C<->), it will
2782                                  # Here we have a primary relation field. Store the field value as  not be in the list returned. The idea here is to get a list of the
2783                                  # a scalar.  keywords the user wants to see. The list will be processed to remove
2784                                  $this->{$name} = eval($codeString);  duplicates.
2785    
2786    It is possible to create a string that confuses this method. For example
2787    
2788        frog toad -frog
2789    
2790    would return both C<frog> and C<toad>. If this is a problem we can deal
2791    with it later.
2792    
2793    =over 4
2794    
2795    =item keywordString
2796    
2797    The keyword string to be parsed.
2798    
2799    =item RETURN
2800    
2801    Returns a list of the words in the keyword string the user wants to
2802    see.
2803    
2804    =back
2805    
2806    =cut
2807    
2808    sub SplitKeywords {
2809        # Get the parameters.
2810        my ($keywordString) = @_;
2811        # Make a safety copy of the string. (This helps during debugging.)
2812        my $workString = $keywordString;
2813        # Convert operators we don't care about to spaces.
2814        $workString =~ tr/+"()<>/ /;
2815        # Split the rest of the string along space boundaries. Note that we
2816        # eliminate any words that are zero length or begin with a minus sign.
2817        my @wordList = grep { $_ && substr($_, 0, 1) ne "-" } split /\s+/, $workString;
2818        # Use a hash to remove duplicates.
2819        my %words = map { $_ => 1 } @wordList;
2820        # Return the result.
2821        return sort keys %words;
2822    }
2823    
2824    =head3 ValidateFieldName
2825    
2826    C<< my $okFlag = ERDB::ValidateFieldName($fieldName); >>
2827    
2828    Return TRUE if the specified field name is valid, else FALSE. Valid field names must
2829    be hyphenated words subject to certain restrictions.
2830    
2831    =over 4
2832    
2833    =item fieldName
2834    
2835    Field name to be validated.
2836    
2837    =item RETURN
2838    
2839    Returns TRUE if the field name is valid, else FALSE.
2840    
2841    =back
2842    
2843    =cut
2844    
2845    sub ValidateFieldName {
2846        # Get the parameters.
2847        my ($fieldName) = @_;
2848        # Declare the return variable. The field name is valid until we hear
2849        # differently.
2850        my $retVal = 1;
2851        # Look for bad stuff in the name.
2852        if ($fieldName =~ /--/) {
2853            # Here we have a doubled minus sign.
2854            Trace("Field name $fieldName has a doubled hyphen.") if T(1);
2855            $retVal = 0;
2856        } elsif ($fieldName !~ /^[A-Za-z]/) {
2857            # Here the field name is missing the initial letter.
2858            Trace("Field name $fieldName does not begin with a letter.") if T(1);
2859            $retVal = 0;
2860                          } else {                          } else {
2861                                  # Here we have a secondary relation field. Create a null list          # Strip out the minus signs. Everything remaining must be a letter,
2862                                  # and push the desired number of field values onto it.          # underscore, or digit.
2863                                  my @fieldValues = ();          my $strippedName = $fieldName;
2864                                  my $count = IntGen(0,$data->{testCount});          $strippedName =~ s/-//g;
2865                                  for (my $i = 0; $i < $count; $i++) {          if ($strippedName !~ /^(\w|\d)+$/) {
2866                                          my $newValue = eval($codeString);              Trace("Field name $fieldName contains illegal characters.") if T(1);
2867                                          push @fieldValues, $newValue;              $retVal = 0;
2868            }
2869        }
2870        # Return the result.
2871        return $retVal;
2872    }
2873    
2874    =head3 ReadMetaXML
2875    
2876    C<< my $rawMetaData = ERDB::ReadDBD($fileName); >>
2877    
2878    This method reads a raw database definition XML file and returns it.
2879    Normally, the metadata used by the ERDB system has been processed and
2880    modified to make it easier to load and retrieve the data; however,
2881    this method can be used to get the data in its raw form.
2882    
2883    =over 4
2884    
2885    =item fileName
2886    
2887    Name of the XML file to read.
2888    
2889    =item RETURN
2890    
2891    Returns a hash reference containing the raw XML data from the specified file.
2892    
2893    =back
2894    
2895    =cut
2896    
2897    sub ReadMetaXML {
2898        # Get the parameters.
2899        my ($fileName) = @_;
2900        # Read the XML.
2901        my $retVal = XML::Simple::XMLin($fileName, %XmlOptions, %XmlInOpts);
2902        Trace("XML metadata loaded from file $fileName.") if T(1);
2903        # Return the result.
2904        return $retVal;
2905    }
2906    
2907    =head3 GetEntityFieldHash
2908    
2909    C<< my $fieldHashRef = ERDB::GetEntityFieldHash($structure, $entityName); >>
2910    
2911    Get the field hash of the named entity in the specified raw XML structure.
2912    The field hash may not exist, in which case we need to create it.
2913    
2914    =over 4
2915    
2916    =item structure
2917    
2918    Raw XML structure defininng the database. This is not the run-time XML used by
2919    an ERDB object, since that has all sorts of optimizations built-in.
2920    
2921    =item entityName
2922    
2923    Name of the entity whose field structure is desired.
2924    
2925    =item RETURN
2926    
2927    Returns the field hash used to define the entity's fields.
2928    
2929    =back
2930    
2931    =cut
2932    
2933    sub GetEntityFieldHash {
2934        # Get the parameters.
2935        my ($structure, $entityName) = @_;
2936        # Get the entity structure.
2937        my $entityData = $structure->{Entities}->{$entityName};
2938        # Look for a field structure.
2939        my $retVal = $entityData->{Fields};
2940        # If it doesn't exist, create it.
2941        if (! defined($retVal)) {
2942            $entityData->{Fields} = {};
2943            $retVal = $entityData->{Fields};
2944                                  }                                  }
2945                                  # Store the value list in the main hash.      # Return the result.
2946                                  $this->{$name} = \@fieldValues;      return $retVal;
2947                          }                          }
2948    
2949    =head3 WriteMetaXML
2950    
2951    C<< ERDB::WriteMetaXML($structure, $fileName); >>
2952    
2953    Write the metadata XML to a file. This method is the reverse of L</ReadMetaXML>, and is
2954    used to update the database definition. It must be used with care, however, since it
2955    will only work on a raw structure, not on the processed structure created by an ERDB
2956    constructor.
2957    
2958    =over 4
2959    
2960    =item structure
2961    
2962    XML structure to be written to the file.
2963    
2964    =item fileName
2965    
2966    Name of the output file to which the updated XML should be stored.
2967    
2968    =back
2969    
2970    =cut
2971    
2972    sub WriteMetaXML {
2973        # Get the parameters.
2974        my ($structure, $fileName) = @_;
2975        # Compute the output.
2976        my $fileString = XML::Simple::XMLout($structure, %XmlOptions, %XmlOutOpts);
2977        # Write it to the file.
2978        my $xmlOut = Open(undef, ">$fileName");
2979        print $xmlOut $fileString;
2980                  }                  }
2981    
2982    
2983    =head3 HTMLNote
2984    
2985    Convert a note or comment to HTML by replacing some bulletin-board codes with HTML. The codes
2986    supported are C<[b]> for B<bold>, C<[i]> for I<italics>, and C<[p]> for a new paragraph.
2987    Except for C<[p]>, all the codes are closed by slash-codes. So, for
2988    example, C<[b]Feature[/b]> displays the string C<Feature> in boldface.
2989    
2990    C<< my $realHtml = ERDB::HTMLNote($dataString); >>
2991    
2992    =over 4
2993    
2994    =item dataString
2995    
2996    String to convert to HTML.
2997    
2998    =item RETURN
2999    
3000    An HTML string derived from the input string.
3001    
3002    =back
3003    
3004    =cut
3005    
3006    sub HTMLNote {
3007        # Get the parameter.
3008        my ($dataString) = @_;
3009        # HTML-escape the text.
3010        my $retVal = CGI::escapeHTML($dataString);
3011        # Substitute the bulletin board codes.
3012        $retVal =~ s!\[(/?[bi])\]!<$1>!g;
3013        $retVal =~ s!\[p\]!</p><p>!g;
3014        # Return the result.
3015        return $retVal;
3016          }          }
3017    
3018    
3019    =head2 Data Mining Methods
3020    
3021    =head3 GetUsefulCrossValues
3022    
3023    C<< my @attrNames = $sprout->GetUsefulCrossValues($sourceEntity, $relationship); >>
3024    
3025    Return a list of the useful attributes that would be returned by a B<Cross> call
3026    from an entity of the source entity type through the specified relationship. This
3027    means it will return the fields of the target entity type and the intersection data
3028    fields in the relationship. Only primary table fields are returned. In other words,
3029    the field names returned will be for fields where there is always one and only one
3030    value.
3031    
3032    =over 4
3033    
3034    =item sourceEntity
3035    
3036    Name of the entity from which the relationship crossing will start.
3037    
3038    =item relationship
3039    
3040    Name of the relationship being crossed.
3041    
3042    =item RETURN
3043    
3044    Returns a list of field names in Sprout field format (I<objectName>C<(>I<fieldName>C<)>.
3045    
3046    =back
3047    
3048    =cut
3049    #: Return Type @;
3050    sub GetUsefulCrossValues {
3051        # Get the parameters.
3052        my ($self, $sourceEntity, $relationship) = @_;
3053        # Declare the return variable.
3054        my @retVal = ();
3055        # Determine the target entity for the relationship. This is whichever entity is not
3056        # the source entity. So, if the source entity is the FROM, we'll get the name of
3057        # the TO, and vice versa.
3058        my $relStructure = $self->_GetStructure($relationship);
3059        my $targetEntityType = ($relStructure->{from} eq $sourceEntity ? "to" : "from");
3060        my $targetEntity = $relStructure->{$targetEntityType};
3061        # Get the field table for the entity.
3062        my $entityFields = $self->GetFieldTable($targetEntity);
3063        # The field table is a hash. The hash key is the field name. The hash value is a structure.
3064        # For the entity fields, the key aspect of the target structure is that the {relation} value
3065        # must match the entity name.
3066        my @fieldList = map { "$targetEntity($_)" } grep { $entityFields->{$_}->{relation} eq $targetEntity }
3067                            keys %{$entityFields};
3068        # Push the fields found onto the return variable.
3069        push @retVal, sort @fieldList;
3070        # Get the field table for the relationship.
3071        my $relationshipFields = $self->GetFieldTable($relationship);
3072        # Here we have a different rule. We want all the fields other than "from-link" and "to-link".
3073        # This may end up being an empty set.
3074        my @fieldList2 = map { "$relationship($_)" } grep { $_ ne "from-link" && $_ ne "to-link" }
3075                            keys %{$relationshipFields};
3076        # Push these onto the return list.
3077        push @retVal, sort @fieldList2;
3078        # Return the result.
3079        return @retVal;
3080    }
3081    
3082    =head3 FindColumn
3083    
3084    C<< my $colIndex = ERDB::FindColumn($headerLine, $columnIdentifier); >>
3085    
3086    Return the location a desired column in a data mining header line. The data
3087    mining header line is a tab-separated list of column names. The column
3088    identifier is either the numerical index of a column or the actual column
3089    name.
3090    
3091    =over 4
3092    
3093    =item headerLine
3094    
3095    The header line from a data mining command, which consists of a tab-separated
3096    list of column names.
3097    
3098    =item columnIdentifier
3099    
3100    Either the ordinal number of the desired column (1-based), or the name of the
3101    desired column.
3102    
3103    =item RETURN
3104    
3105    Returns the array index (0-based) of the desired column.
3106    
3107    =back
3108    
3109    =cut
3110    
3111    sub FindColumn {
3112        # Get the parameters.
3113        my ($headerLine, $columnIdentifier) = @_;
3114        # Declare the return variable.
3115        my $retVal;
3116        # Split the header line into column names.
3117        my @headers = ParseColumns($headerLine);
3118        # Determine whether we have a number or a name.
3119        if ($columnIdentifier =~ /^\d+$/) {
3120            # Here we have a number. Subtract 1 and validate the result.
3121            $retVal = $columnIdentifier - 1;
3122            if ($retVal < 0 || $retVal > $#headers) {
3123                Confess("Invalid column identifer \"$columnIdentifier\": value out of range.");
3124            }
3125        } else {
3126            # Here we have a name. We need to find it in the list.
3127            for (my $i = 0; $i <= $#headers && ! defined($retVal); $i++) {
3128                if ($headers[$i] eq $columnIdentifier) {
3129                    $retVal = $i;
3130                }
3131            }
3132            if (! defined($retVal)) {
3133                Confess("Invalid column identifier \"$columnIdentifier\": value not found.");
3134            }
3135        }
3136        # Return the result.
3137        return $retVal;
3138    }
3139    
3140    =head3 ParseColumns
3141    
3142    C<< my @columns = ERDB::ParseColumns($line); >>
3143    
3144    Convert the specified data line to a list of columns.
3145    
3146    =over 4
3147    
3148    =item line
3149    
3150    A data mining input, consisting of a tab-separated list of columns terminated by a
3151    new-line.
3152    
3153    =item RETURN
3154    
3155    Returns a list consisting of the column values.
3156    
3157    =back
3158    
3159    =cut
3160    
3161    sub ParseColumns {
3162        # Get the parameters.
3163        my ($line) = @_;
3164        # Chop off the line-end.
3165        chomp $line;
3166        # Split it into a list.
3167        my @retVal = split(/\t/, $line);
3168        # Return the result.
3169        return @retVal;
3170    }
3171    
3172    =head2 Virtual Methods
3173    
3174    =head3 CleanKeywords
3175    
3176    C<< my $cleanedString = $erdb->CleanKeywords($searchExpression); >>
3177    
3178    Clean up a search expression or keyword list. This is a virtual method that may
3179    be overridden by the subclass. The base-class method removes extra spaces
3180    and converts everything to lower case.
3181    
3182    =over 4
3183    
3184    =item searchExpression
3185    
3186    Search expression or keyword list to clean. Note that a search expression may
3187    contain boolean operators which need to be preserved. This includes leading
3188    minus signs.
3189    
3190    =item RETURN
3191    
3192    Cleaned expression or keyword list.
3193    
3194    =back
3195    
3196    =cut
3197    
3198    sub CleanKeywords {
3199        # Get the parameters.
3200        my ($self, $searchExpression) = @_;
3201        # Lower-case the expression and copy it into the return variable. Note that we insure we
3202        # don't accidentally end up with an undefined value.
3203        my $retVal = lc($searchExpression || "");
3204        # Remove extra spaces.
3205        $retVal =~ s/\s+/ /g;
3206        $retVal =~ s/(^\s+)|(\s+$)//g;
3207        # Return the result.
3208        return $retVal;
3209    }
3210    
3211    =head3 GetSourceObject
3212    
3213    C<< my $source = $erdb->GetSourceObject($entityName); >>
3214    
3215    Return the object to be used in loading special attributes of the specified entity. The
3216    algorithm for loading special attributes is stored in the C<DataGen> elements of the
3217    XML
3218    
3219    =head2 Internal Utility Methods
3220    
3221    =head3 _RelationMap
3222    
3223    C<< my @relationMap = _RelationMap($mappedNameHashRef, $mappedNameListRef); >>
3224    
3225    Create the relation map for an SQL query. The relation map is used by B<DBObject>
3226    to determine how to interpret the results of the query.
3227    
3228    =over 4
3229    
3230    =item mappedNameHashRef
3231    
3232    Reference to a hash that maps modified object names to real object names.
3233    
3234    =item mappedNameListRef
3235    
3236    Reference to a list of modified object names in the order they appear in the
3237    SELECT list.
3238    
3239    =item RETURN
3240    
3241    Returns a list of 2-tuples. Each tuple consists of an object name as used in the
3242    query followed by the actual name of that object. This enables the B<DBObject> to
3243    determine the order of the tables in the query and which object name belongs to each
3244    mapped object name. Most of the time these two values are the same; however, if a
3245    relation occurs twice in the query, the relation name in the field list and WHERE
3246    clause will use a mapped name (generally the actual relation name with a numeric
3247    suffix) that does not match the actual relation name.
3248    
3249    =back
3250    
3251    =cut
3252    
3253    sub _RelationMap {
3254        # Get the parameters.
3255        my ($mappedNameHashRef, $mappedNameListRef) = @_;
3256        # Declare the return variable.
3257        my @retVal = ();
3258        # Build the map.
3259        for my $mappedName (@{$mappedNameListRef}) {
3260            push @retVal, [$mappedName, $mappedNameHashRef->{$mappedName}];
3261        }
3262        # Return it.
3263        return @retVal;
3264    }
3265    
3266    
3267    =head3 _SetupSQL
3268    
3269    Process a list of object names and a filter clause so that they can be used to
3270    build an SQL statement. This method takes in a reference to a list of object names
3271    and a filter clause. It will return a corrected filter clause, a list of mapped
3272    names and the mapped name hash.
3273    
3274    This is an instance method.
3275    
3276    =over 4
3277    
3278    =item objectNames
3279    
3280    Reference to a list of the object names to be included in the query.
3281    
3282    =item filterClause
3283    
3284    A string containing the WHERE clause for the query (without the C<WHERE>) and also
3285    optionally the C<ORDER BY> and C<LIMIT> clauses.
3286    
3287    =item matchClause
3288    
3289    An optional full-text search clause. If specified, it will be inserted at the
3290    front of the WHERE clause. It should already be SQL-formatted; that is, the
3291    field names should be in the form I<table>C<.>I<fieldName>.
3292    
3293    =item RETURN
3294    
3295    Returns a three-element list. The first element is the SQL statement suffix, beginning
3296    with the FROM clause. The second element is a reference to a list of the names to be
3297    used in retrieving the fields. The third element is a hash mapping the names to the
3298    objects they represent.
3299    
3300    =back
3301    
3302    =cut
3303    
3304    sub _SetupSQL {
3305        my ($self, $objectNames, $filterClause, $matchClause) = @_;
3306        # Adjust the list of object names to account for multiple occurrences of the
3307        # same object. We start with a hash table keyed on object name that will
3308        # return the object suffix. The first time an object is encountered it will
3309        # not be found in the hash. The next time the hash will map the object name
3310        # to 2, then 3, and so forth.
3311        my %objectHash = ();
3312        # This list will contain the object names as they are to appear in the
3313        # FROM list.
3314        my @fromList = ();
3315        # This list contains the suffixed object name for each object. It is exactly
3316        # parallel to the list in the $objectNames parameter.
3317        my @mappedNameList = ();
3318        # Finally, this hash translates from a mapped name to its original object name.
3319        my %mappedNameHash = ();
3320        # Now we create the lists. Note that for every single name we push something into
3321        # @fromList and @mappedNameList. This insures that those two arrays are exactly
3322        # parallel to $objectNames.
3323        for my $objectName (@{$objectNames}) {
3324            # Get the next suffix for this object.
3325            my $suffix = $objectHash{$objectName};
3326            if (! $suffix) {
3327                # Here we are seeing the object for the first time. The object name
3328                # is used as is.
3329                push @mappedNameList, $objectName;
3330                push @fromList, $objectName;
3331                $mappedNameHash{$objectName} = $objectName;
3332                # Denote the next suffix will be 2.
3333                $objectHash{$objectName} = 2;
3334            } else {
3335                # Here we've seen the object before. We construct a new name using
3336                # the suffix from the hash and update the hash.
3337                my $mappedName = "$objectName$suffix";
3338                $objectHash{$objectName} = $suffix + 1;
3339                # The FROM list has the object name followed by the mapped name. This
3340                # tells SQL it's still the same table, but we're using a different name
3341                # for it to avoid confusion.
3342                push @fromList, "$objectName $mappedName";
3343                # The mapped-name list contains the real mapped name.
3344                push @mappedNameList, $mappedName;
3345                # Finally, enable us to get back from the mapped name to the object name.
3346                $mappedNameHash{$mappedName} = $objectName;
3347            }
3348        }
3349        # Begin the SELECT suffix. It starts with
3350        #
3351        # FROM name1, name2, ... nameN
3352        #
3353        my $suffix = "FROM " . join(', ', @fromList);
3354        # Now for the WHERE. First, we need a place for the filter string.
3355        my $filterString = "";
3356        # We will also keep a list of conditions to add to the WHERE clause in order to link
3357        # entities and relationships as well as primary relations to secondary ones.
3358        my @joinWhere = ();
3359        # Check for a filter clause.
3360        if ($filterClause) {
3361            # Here we have one, so we convert its field names and add it to the query. First,
3362            # We create a copy of the filter string we can work with.
3363            $filterString = $filterClause;
3364            # Next, we sort the object names by length. This helps protect us from finding
3365            # object names inside other object names when we're doing our search and replace.
3366            my @sortedNames = sort { length($b) - length($a) } @mappedNameList;
3367            # The final preparatory step is to create a hash table of relation names. The
3368            # table begins with the relation names already in the SELECT command. We may
3369            # need to add relations later if there is filtering on a field in a secondary
3370            # relation. The secondary relations are the ones that contain multiply-
3371            # occurring or optional fields.
3372            my %fromNames = map { $_ => 1 } @sortedNames;
3373            # We are ready to begin. We loop through the object names, replacing each
3374            # object name's field references by the corresponding SQL field reference.
3375            # Along the way, if we find a secondary relation, we will need to add it
3376            # to the FROM clause.
3377            for my $mappedName (@sortedNames) {
3378                # Get the length of the object name plus 2. This is the value we add to the
3379                # size of the field name to determine the size of the field reference as a
3380                # whole.
3381                my $nameLength = 2 + length $mappedName;
3382                # Get the real object name for this mapped name.
3383                my $objectName = $mappedNameHash{$mappedName};
3384                Trace("Processing $mappedName for object $objectName.") if T(4);
3385                # Get the object's field list.
3386                my $fieldList = $self->GetFieldTable($objectName);
3387                # Find the field references for this object.
3388                while ($filterString =~ m/$mappedName\(([^)]*)\)/g) {
3389                    # At this point, $1 contains the field name, and the current position
3390                    # is set immediately after the final parenthesis. We pull out the name of
3391                    # the field and the position and length of the field reference as a whole.
3392                    my $fieldName = $1;
3393                    my $len = $nameLength + length $fieldName;
3394                    my $pos = pos($filterString) - $len;
3395                    # Insure the field exists.
3396                    if (!exists $fieldList->{$fieldName}) {
3397                        Confess("Field $fieldName not found for object $objectName.");
3398                    } else {
3399                        Trace("Processing $fieldName at position $pos.") if T(4);
3400                        # Get the field's relation.
3401                        my $relationName = $fieldList->{$fieldName}->{relation};
3402                        # Now we have a secondary relation. We need to insure it matches the
3403                        # mapped name of the primary relation. First we peel off the suffix
3404                        # from the mapped name.
3405                        my $mappingSuffix = substr $mappedName, length($objectName);
3406                        # Put the mapping suffix onto the relation name to get the
3407                        # mapped relation name.
3408                        my $mappedRelationName = "$relationName$mappingSuffix";
3409                        # Insure the relation is in the FROM clause.
3410                        if (!exists $fromNames{$mappedRelationName}) {
3411                            # Add the relation to the FROM clause.
3412                            if ($mappedRelationName eq $relationName) {
3413                                # The name is un-mapped, so we add it without
3414                                # any frills.
3415                                $suffix .= ", $relationName";
3416                                push @joinWhere, "$objectName.id = $relationName.id";
3417                            } else {
3418                                # Here we have a mapping situation.
3419                                $suffix .= ", $relationName $mappedRelationName";
3420                                push @joinWhere, "$mappedRelationName.id = $mappedName.id";
3421                            }
3422                            # Denote we have this relation available for future fields.
3423                            $fromNames{$mappedRelationName} = 1;
3424                        }
3425                        # Form an SQL field reference from the relation name and the field name.
3426                        my $sqlReference = "$mappedRelationName." . _FixName($fieldName);
3427                        # Put it into the filter string in place of the old value.
3428                        substr($filterString, $pos, $len) = $sqlReference;
3429                        # Reposition the search.
3430                        pos $filterString = $pos + length $sqlReference;
3431                    }
3432                }
3433            }
3434        }
3435        # The next step is to join the objects together. We only need to do this if there
3436        # is more than one object in the object list. We start with the first object and
3437        # run through the objects after it. Note also that we make a safety copy of the
3438        # list before running through it, because we shift off the first object before
3439        # processing the rest.
3440        my @mappedObjectList = @mappedNameList;
3441        my $lastMappedObject = shift @mappedObjectList;
3442        # Get the join table.
3443        my $joinTable = $self->{_metaData}->{Joins};
3444        # Loop through the object list.
3445        for my $thisMappedObject (@mappedObjectList) {
3446            # Look for a join using the real object names.
3447            my $lastObject = $mappedNameHash{$lastMappedObject};
3448            my $thisObject = $mappedNameHash{$thisMappedObject};
3449            my $joinKey = "$lastObject/$thisObject";
3450            if (!exists $joinTable->{$joinKey}) {
3451                # Here there's no join, so we throw an error.
3452                Confess("No join exists to connect from $lastMappedObject to $thisMappedObject.");
3453            } else {
3454                # Get the join clause.
3455                my $unMappedJoin = $joinTable->{$joinKey};
3456                # Fix the names.
3457                $unMappedJoin =~ s/$lastObject/$lastMappedObject/;
3458                $unMappedJoin =~ s/$thisObject/$thisMappedObject/;
3459                push @joinWhere, $unMappedJoin;
3460                # Save this object as the last object for the next iteration.
3461                $lastMappedObject = $thisMappedObject;
3462            }
3463        }
3464        # Now we need to handle the whole ORDER BY / LIMIT thing. The important part
3465        # here is we want the filter clause to be empty if there's no WHERE filter.
3466        # We'll put the ORDER BY / LIMIT clauses in the following variable.
3467        my $orderClause = "";
3468        # This is only necessary if we have a filter string in which the ORDER BY
3469        # and LIMIT clauses can live.
3470        if ($filterString) {
3471            # Locate the ORDER BY or LIMIT verbs (if any). We use a non-greedy
3472            # operator so that we find the first occurrence of either verb.
3473            if ($filterString =~ m/^(.*?)\s*(ORDER BY|LIMIT)/g) {
3474                # Here we have an ORDER BY or LIMIT verb. Split it off of the filter string.
3475                my $pos = pos $filterString;
3476                $orderClause = $2 . substr($filterString, $pos);
3477                $filterString = $1;
3478            }
3479        }
3480        # All the things that are supposed to be in the WHERE clause of the
3481        # SELECT command need to be put into @joinWhere so we can string them
3482        # together. We begin with the match clause. This is important,
3483        # because the match clause's parameter mark must precede any parameter
3484        # marks in the filter string.
3485        if ($matchClause) {
3486            push @joinWhere, $matchClause;
3487        }
3488        # Add the filter string. We put it in parentheses to avoid operator
3489        # precedence problems with the match clause or the joins.
3490        if ($filterString) {
3491            Trace("Filter string is \"$filterString\".") if T(4);
3492            push @joinWhere, "($filterString)";
3493        }
3494        # String it all together into a big filter clause.
3495        if (@joinWhere) {
3496            $suffix .= " WHERE " . join(' AND ', @joinWhere);
3497        }
3498        # Add the sort or limit clause (if any).
3499        if ($orderClause) {
3500            $suffix .= " $orderClause";
3501        }
3502        # Return the suffix, the mapped name list, and the mapped name hash.
3503        return ($suffix, \@mappedNameList, \%mappedNameHash);
3504    }
3505    
3506    =head3 _GetStatementHandle
3507    
3508    This method will prepare and execute an SQL query, returning the statement handle.
3509    The main reason for doing this here is so that everybody who does SQL queries gets
3510    the benefit of tracing.
3511    
3512    This is an instance method.
3513    
3514    =over 4
3515    
3516    =item command
3517    
3518    Command to prepare and execute.
3519    
3520    =item params
3521    
3522    Reference to a list of the values to be substituted in for the parameter marks.
3523    
3524    =item RETURN
3525    
3526    Returns a prepared and executed statement handle from which the caller can extract
3527    results.
3528    
3529    =back
3530    
3531    =cut
3532    
3533    sub _GetStatementHandle {
3534        # Get the parameters.
3535        my ($self, $command, $params) = @_;
3536        # Trace the query.
3537        Trace("SQL query: $command") if T(SQL => 3);
3538        Trace("PARMS: '" . (join "', '", @{$params}) . "'") if (T(SQL => 4) && (@{$params} > 0));
3539        # Get the database handle.
3540        my $dbh = $self->{_dbh};
3541        # Prepare the command.
3542        my $sth = $dbh->prepare_command($command);
3543        # Execute it with the parameters bound in.
3544        $sth->execute(@{$params}) || Confess("SELECT error:  " . $sth->errstr());
3545        # Return the statement handle.
3546        return $sth;
3547    }
3548    
3549    =head3 _GetLoadStats
3550    
3551    Return a blank statistics object for use by the load methods.
3552    
3553    This is a static method.
3554    
3555    =cut
3556    
3557    sub _GetLoadStats{
3558        return Stats->new();
3559  }  }
3560    
3561  =head3 DumpRelation  =head3 _DumpRelation
3562    
3563  Dump the specified relation's to the specified output file in tab-delimited format.  Dump the specified relation to the specified output file in tab-delimited format.
3564    
3565  This is an instance method.  This is an instance method.
3566    
# Line 1417  Line 3608 
3608          close DTXOUT;          close DTXOUT;
3609  }  }
3610    
3611  =head3 GetStructure  =head3 _GetStructure
3612    
3613  Get the data structure for a specified entity or relationship.  Get the data structure for a specified entity or relationship.
3614    
# Line 1456  Line 3647 
3647          return $retVal;          return $retVal;
3648  }  }
3649    
3650  =head3 GetRelationTable  
3651    
3652    =head3 _GetRelationTable
3653    
3654  Get the list of relations for a specified entity or relationship.  Get the list of relations for a specified entity or relationship.
3655    
# Line 1485  Line 3678 
3678          return $objectData->{Relations};          return $objectData->{Relations};
3679  }  }
3680    
3681  =head3 GetFieldTable  =head3 _ValidateFieldNames
   
 Get the field structure for a specified entity or relationship.  
   
 This is an instance method.  
   
 =over 4  
   
 =item objectName  
   
 Name of the desired entity or relationship.  
   
 =item RETURN  
   
 The table containing the field descriptors for the specified object.  
   
 =back  
   
 =cut  
   
 sub _GetFieldTable {  
         # Get the parameters.  
         my ($self, $objectName) = @_;  
         # Get the descriptor from the metadata.  
         my $objectData = $self->_GetStructure($objectName);  
         # Return the object's field table.  
         return $objectData->{Fields};  
 }  
   
 =head3 ValidateFieldNames  
3682    
3683  Determine whether or not the field names are valid. A description of the problems with the names  Determine whether or not the field names are valid. A description of the problems with the names
3684  will be written to the standard error output. If there is an error, this method will abort. This is  will be written to the standard error output. If there is an error, this method will abort. This is
# Line 1541  Line 3705 
3705                  for my $object (values %{$metadata->{$section}}) {                  for my $object (values %{$metadata->{$section}}) {
3706                          # Loop through the object's fields.                          # Loop through the object's fields.
3707                          for my $fieldName (keys %{$object->{Fields}}) {                          for my $fieldName (keys %{$object->{Fields}}) {
3708                                  # Now we make some initial validations.                  # If this field name is invalid, set the return value to zero
3709                                  if ($fieldName =~ /--/) {                  # so we know we encountered an error.
3710                                          # Here we have a doubled minus sign.                  if (! ValidateFieldName($fieldName)) {
                                         print STDERR "Field name $fieldName has a doubled hyphen.\n";  
                                         $retVal = 0;  
                                 } elsif ($fieldName !~ /^[A-Za-z]/) {  
                                         # Here the field name is missing the initial letter.  
                                         print STDERR "Field name $fieldName does not begin with a letter.\n";  
                                         $retVal = 0;  
                                 } else {  
                                         # Strip out the minus signs. Everything remaining must be a letter  
                                         # or digit.  
                                         my $strippedName = $fieldName;  
                                         $strippedName =~ s/-//g;  
                                         if ($strippedName !~ /^[A-Za-z0-9]+$/) {  
                                                 print STDERR "Field name $fieldName contains illegal characters.\n";  
3711                                                  $retVal = 0;                                                  $retVal = 0;
3712                                          }                                          }
3713                                  }                                  }
3714                          }                          }
3715                  }                  }
         }  
3716          # If an error was found, fail.          # If an error was found, fail.
3717          if ($retVal  == 0) {          if ($retVal  == 0) {
3718                  Confess("Errors found in field names.");                  Confess("Errors found in field names.");
3719          }          }
3720  }  }
3721    
3722  =head3 LoadRelation  =head3 _LoadRelation
3723    
3724  Load a relation from the data in a tab-delimited disk file. The load will only take place if a disk  Load a relation from the data in a tab-delimited disk file. The load will only take place if a disk
3725  file with the same name as the relation exists in the specified directory.  file with the same name as the relation exists in the specified directory.
# Line 1629  Line 3779 
3779          return $retVal;          return $retVal;
3780  }  }
3781    
3782  =head3 LoadMetaData  
3783    =head3 _LoadMetaData
3784    
3785  This method loads the data describing this database from an XML file into a metadata structure.  This method loads the data describing this database from an XML file into a metadata structure.
3786  The resulting structure is a set of nested hash tables containing all the information needed to  The resulting structure is a set of nested hash tables containing all the information needed to
# Line 1654  Line 3805 
3805  sub _LoadMetaData {  sub _LoadMetaData {
3806          # Get the parameters.          # Get the parameters.
3807          my ($filename) = @_;          my ($filename) = @_;
3808        Trace("Reading DBD from $filename.") if T(2);
3809          # Slurp the XML file into a variable. Extensive use of options is used to insure we          # Slurp the XML file into a variable. Extensive use of options is used to insure we
3810          # get the exact structure we want.          # get the exact structure we want.
3811          my $metadata = XML::Simple::XMLin($filename,      my $metadata = ReadMetaXML($filename);
                                                                           GroupTags => { Relationships => 'Relationship',  
                                                                                                      Entities => 'Entity',  
                                                                                                          Fields => 'Field',  
                                                                                                          Indexes => 'Index',  
                                                                                                          IndexFields => 'IndexField'},  
                                                                           KeyAttr => { Relationship => 'name',  
                                                                                                    Entity => 'name',  
                                                                                                    Field => 'name'},  
                                                                           ForceArray => ['Field', 'Index', 'IndexField'],  
                                                                           ForceContent => 1,  
                                                                           NormalizeSpace => 2  
                                                                           );  
         Trace("XML metadata loaded from file $filename.") if T(1);  
3812          # Before we go any farther, we need to validate the field and object names. If an error is found,          # Before we go any farther, we need to validate the field and object names. If an error is found,
3813          # the method below will fail.          # the method below will fail.
3814          _ValidateFieldNames($metadata);          _ValidateFieldNames($metadata);
# Line 1681  Line 3820 
3820          for my $entityName (keys %{$entityList}) {          for my $entityName (keys %{$entityList}) {
3821                  my $entityStructure = $entityList->{$entityName};                  my $entityStructure = $entityList->{$entityName};
3822                  #                  #
3823                  # The first step is to run creating all the entity's default values. For C<Field> elements,          # The first step is to create all the entity's default values. For C<Field> elements,
3824                  # the relation name must be added where it is not specified. For relationships,                  # the relation name must be added where it is not specified. For relationships,
3825                  # the B<from-link> and B<to-link> fields must be inserted, and for entities an B<id>                  # the B<from-link> and B<to-link> fields must be inserted, and for entities an B<id>
3826                  # field must be added to each relation. Finally, each field will have a C<PrettySort> attribute                  # field must be added to each relation. Finally, each field will have a C<PrettySort> attribute
# Line 1799  Line 3938 
3938                          my $count = 0;                          my $count = 0;
3939                          for my $index (@{$indexList}) {                          for my $index (@{$indexList}) {
3940                                  # Add this index to the index table.                                  # Add this index to the index table.
3941                                  _AddIndex("idx$relationName$count", $relation, $index);                  _AddIndex("idx$count", $relation, $index);
3942                                  # Increment the counter so that the next index has a different name.                                  # Increment the counter so that the next index has a different name.
3943                                  $count++;                                  $count++;
3944                          }                          }
# Line 1860  Line 3999 
3999                  my @fromList = ();                  my @fromList = ();
4000                  my @toList = ();                  my @toList = ();
4001                  my @bothList = ();                  my @bothList = ();
4002                  Trace("Join table build for $entityName.") if T(3);          Trace("Join table build for $entityName.") if T(metadata => 4);
4003                  for my $relationshipName (keys %{$relationshipList}) {                  for my $relationshipName (keys %{$relationshipList}) {
4004                          my $relationship = $relationshipList->{$relationshipName};                          my $relationship = $relationshipList->{$relationshipName};
4005                          # Determine if this relationship has our entity in one of its link fields.                          # Determine if this relationship has our entity in one of its link fields.
4006                          my $fromEntity = $relationship->{from};                          my $fromEntity = $relationship->{from};
4007                          my $toEntity = $relationship->{to};                          my $toEntity = $relationship->{to};
4008                          Trace("Join check for relationship $relationshipName from $fromEntity to $toEntity.") if T(3);              Trace("Join check for relationship $relationshipName from $fromEntity to $toEntity.") if T(Joins => 4);
4009                          if ($fromEntity eq $entityName) {                          if ($fromEntity eq $entityName) {
4010                                  if ($toEntity eq $entityName) {                                  if ($toEntity eq $entityName) {
4011                                          # Here the relationship is recursive.                                          # Here the relationship is recursive.
4012                                          push @bothList, $relationshipName;                                          push @bothList, $relationshipName;
4013                                          Trace("Relationship $relationshipName put in both-list.") if T(3);                      Trace("Relationship $relationshipName put in both-list.") if T(metadata => 4);
4014                                  } else {                                  } else {
4015                                          # Here the relationship comes from the entity.                                          # Here the relationship comes from the entity.
4016                                          push @fromList, $relationshipName;                                          push @fromList, $relationshipName;
4017                                          Trace("Relationship $relationshipName put in from-list.") if T(3);                      Trace("Relationship $relationshipName put in from-list.") if T(metadata => 4);
4018                                  }                                  }
4019                          } elsif ($toEntity eq $entityName) {                          } elsif ($toEntity eq $entityName) {
4020                                  # Here the relationship goes to the entity.                                  # Here the relationship goes to the entity.
4021                                  push @toList, $relationshipName;                                  push @toList, $relationshipName;
4022                                  Trace("Relationship $relationshipName put in to-list.") if T(3);                  Trace("Relationship $relationshipName put in to-list.") if T(metadata => 4);
4023                          }                          }
4024                  }                  }
4025                  # Create the nonrecursive joins. Note that we build two hashes for running                  # Create the nonrecursive joins. Note that we build two hashes for running
# Line 1896  Line 4035 
4035                                  # Create joins between the entity and this relationship.                                  # Create joins between the entity and this relationship.
4036                                  my $linkField = "$relationshipName.${linkType}_link";                                  my $linkField = "$relationshipName.${linkType}_link";
4037                                  my $joinClause = "$entityName.id = $linkField";                                  my $joinClause = "$entityName.id = $linkField";
4038                                  Trace("Entity join clause is $joinClause for $entityName and $relationshipName.") if T(4);                  Trace("Entity join clause is $joinClause for $entityName and $relationshipName.") if T(metadata => 4);
4039                                  $joinTable{"$entityName/$relationshipName"} = $joinClause;                                  $joinTable{"$entityName/$relationshipName"} = $joinClause;
4040                                  $joinTable{"$relationshipName/$entityName"} = $joinClause;                                  $joinTable{"$relationshipName/$entityName"} = $joinClause;
4041                                  # Create joins between this relationship and the other relationships.                                  # Create joins between this relationship and the other relationships.
# Line 1917  Line 4056 
4056                                                          # relationship and itself are prohibited.                                                          # relationship and itself are prohibited.
4057                                                          my $relJoinClause = "$otherName.${otherType}_link = $linkField";                                                          my $relJoinClause = "$otherName.${otherType}_link = $linkField";
4058                                                          $joinTable{$joinKey} = $relJoinClause;                                                          $joinTable{$joinKey} = $relJoinClause;
4059                                                          Trace("Relationship join clause is $relJoinClause for $joinKey.") if T(4);                              Trace("Relationship join clause is $relJoinClause for $joinKey.") if T(metadata => 4);
4060                                                  }                                                  }
4061                                          }                                          }
4062                                  }                                  }
# Line 1926  Line 4065 
4065                                  # relationship can only be ambiguous with another recursive relationship,                                  # relationship can only be ambiguous with another recursive relationship,
4066                                  # and the incoming relationship from the outer loop is never recursive.                                  # and the incoming relationship from the outer loop is never recursive.
4067                                  for my $otherName (@bothList) {                                  for my $otherName (@bothList) {
4068                                          Trace("Setting up relationship joins to recursive relationship $otherName with $relationshipName.") if T(3);                      Trace("Setting up relationship joins to recursive relationship $otherName with $relationshipName.") if T(metadata => 4);
4069                                          # Join from the left.                                          # Join from the left.
4070                                          $joinTable{"$relationshipName/$otherName"} =                                          $joinTable{"$relationshipName/$otherName"} =
4071                                                  "$linkField = $otherName.from_link";                                                  "$linkField = $otherName.from_link";
# Line 1941  Line 4080 
4080                  # rise to situations where we can't create the path we want; however, it is always                  # rise to situations where we can't create the path we want; however, it is always
4081                  # possible to get the same effect using multiple queries.                  # possible to get the same effect using multiple queries.
4082                  for my $relationshipName (@bothList) {                  for my $relationshipName (@bothList) {
4083                          Trace("Setting up entity joins to recursive relationship $relationshipName with $entityName.") if T(3);              Trace("Setting up entity joins to recursive relationship $relationshipName with $entityName.") if T(metadata => 4);
4084                          # Join to the entity from each direction.                          # Join to the entity from each direction.
4085                          $joinTable{"$entityName/$relationshipName"} =                          $joinTable{"$entityName/$relationshipName"} =
4086                                  "$entityName.id = $relationshipName.from_link";                                  "$entityName.id = $relationshipName.from_link";
# Line 1955  Line 4094 
4094          return $metadata;          return $metadata;
4095  }  }
4096    
4097  =head3 CreateRelationshipIndex  =head3 _CreateRelationshipIndex
4098    
4099  Create an index for a relationship's relation.  Create an index for a relationship's relation.
4100    
# Line 1992  Line 4131 
4131          # index descriptor does not exist, it will be created automatically so we can add          # index descriptor does not exist, it will be created automatically so we can add
4132          # the field to it.          # the field to it.
4133          unshift @{$newIndex->{IndexFields}}, $firstField;          unshift @{$newIndex->{IndexFields}}, $firstField;
4134        # If this is a one-to-many relationship, the "To" index is unique.
4135        if ($relationshipStructure->{arity} eq "1M" && $indexKey eq "To") {
4136            $newIndex->{Unique} = 'true';
4137        }
4138          # Add the index to the relation.          # Add the index to the relation.
4139          _AddIndex("idx$relationshipName$indexKey", $relationStructure, $newIndex);      _AddIndex("idx$indexKey", $relationStructure, $newIndex);
4140  }  }
4141    
4142  =head3 AddIndex  =head3 _AddIndex
4143    
4144  Add an index to a relation structure.  Add an index to a relation structure.
4145    
# Line 2042  Line 4185 
4185          $relationStructure->{Indexes}->{$indexName} = $newIndex;          $relationStructure->{Indexes}->{$indexName} = $newIndex;
4186  }  }
4187    
4188  =head3 FixupFields  =head3 _FixupFields
4189    
4190  This method fixes the field list for an entity or relationship. It will add the caller-specified  This method fixes the field list for an entity or relationship. It will add the caller-specified
4191  relation name to fields that do not have a name and set the C<PrettySort> value as specified.  relation name to fields that do not have a name and set the C<PrettySort> value as specified.
# Line 2080  Line 4223 
4223                  # Here it doesn't, so we create a new one.                  # Here it doesn't, so we create a new one.
4224                  $structure->{Fields} = { };                  $structure->{Fields} = { };
4225          } else {          } else {
4226                  # Here we have a field list. Loop through its fields.          # Here we have a field list. We need to track the searchable fields, so we
4227            # create a list for stashing them.
4228            my @textFields = ();
4229            # Loop through the fields.
4230                  my $fieldStructures = $structure->{Fields};                  my $fieldStructures = $structure->{Fields};
4231                  for my $fieldName (keys %{$fieldStructures}) {                  for my $fieldName (keys %{$fieldStructures}) {
4232                Trace("Processing field $fieldName of $defaultRelationName.") if T(4);
4233                          my $fieldData = $fieldStructures->{$fieldName};                          my $fieldData = $fieldStructures->{$fieldName};
4234                          # Get the field type.                          # Get the field type.
4235                          my $type = $fieldData->{type};                          my $type = $fieldData->{type};
4236                          # Plug in a relation name if it is needed.                          # Plug in a relation name if it is needed.
4237                          Tracer::MergeOptions($fieldData, { relation => $defaultRelationName });                          Tracer::MergeOptions($fieldData, { relation => $defaultRelationName });
4238                          # Plug in a data generator if we need one.              # Check for searchability.
4239                          if (!exists $fieldData->{DataGen}) {              if ($fieldData->{searchable}) {
4240                                  # The data generator will use the default for the field's type.                  # Only allow this for a primary relation.
4241                                  $fieldData->{DataGen} = { content => $TypeTable{$type}->{dataGen} };                  if ($fieldData->{relation} ne $defaultRelationName) {
4242                        Confess("Field $fieldName of $defaultRelationName is in secondary relations and cannot be searchable.");
4243                    } else {
4244                        push @textFields, $fieldName;
4245                    }
4246                          }                          }
                         # Plug in the defaults for the optional data generation parameters.  
                         Tracer::MergeOptions($fieldData->{DataGen}, { testCount => 1, pass => 0 });  
4247                          # Add the PrettySortValue.                          # Add the PrettySortValue.
4248                          $fieldData->{PrettySort} = (($type eq "text") ? $textPrettySortValue : $prettySortValue);                          $fieldData->{PrettySort} = (($type eq "text") ? $textPrettySortValue : $prettySortValue);
4249                  }                  }
4250            # If there are searchable fields, remember the fact.
4251            if (@textFields) {
4252                $structure->{searchFields} = \@textFields;
4253            }
4254          }          }
4255  }  }
4256    
4257  =head3 FixName  =head3 _FixName
4258    
4259  Fix the incoming field name so that it is a legal SQL column name.  Fix the incoming field name so that it is a legal SQL column name.
4260    
# Line 2130  Line 4283 
4283          return $fieldName;          return $fieldName;
4284  }  }
4285    
4286  =head3 FixNames  =head3 _FixNames
4287    
4288  Fix all the field names in a list.  Fix all the field names in a list.
4289    
# Line 2161  Line 4314 
4314          return @result;          return @result;
4315  }  }
4316    
4317  =head3 AddField  =head3 _AddField
4318    
4319  Add a field to a field list.  Add a field to a field list.
4320    
# Line 2196  Line 4349 
4349          $fieldList->{$fieldName} = $fieldStructure;          $fieldList->{$fieldName} = $fieldStructure;
4350  }  }
4351    
4352  =head3 ReOrderRelationTable  =head3 _ReOrderRelationTable
4353    
4354  This method will take a relation table and re-sort it according to the implicit ordering of the  This method will take a relation table and re-sort it according to the implicit ordering of the
4355  C<PrettySort> property. Instead of a hash based on field names, it will return a list of fields.  C<PrettySort> property. Instead of a hash based on field names, it will return a list of fields.
# Line 2257  Line 4410 
4410    
4411  }  }
4412    
4413  =head3 IsPrimary  =head3 _IsPrimary
4414    
4415  Return TRUE if a specified relation is a primary relation, else FALSE. A relation is primary  Return TRUE if a specified relation is a primary relation, else FALSE. A relation is primary
4416  if it has the same name as an entity or relationship.  if it has the same name as an entity or relationship.
# Line 2293  Line 4446 
4446          return $retVal;          return $retVal;
4447  }  }
4448    
4449  =head3 FindRelation  =head3 _FindRelation
4450    
4451  Return the descriptor for the specified relation.  Return the descriptor for the specified relation.
4452    
# Line 2324  Line 4477 
4477    
4478  =head2 HTML Documentation Utility Methods  =head2 HTML Documentation Utility Methods
4479    
4480  =head3 ComputeRelationshipSentence  =head3 _ComputeRelationshipSentence
4481    
4482  The relationship sentence consists of the relationship name between the names of the  The relationship sentence consists of the relationship name between the names of the
4483  two related entities and an arity indicator.  two related entities and an arity indicator.
# Line 2362  Line 4515 
4515          return $result;          return $result;
4516  }  }
4517    
4518  =head3 ComputeRelationshipHeading  =head3 _ComputeRelationshipHeading
4519    
4520  The relationship heading is the L<relationship sentence|/ComputeRelationshipSentence> with the entity  The relationship heading is the L<relationship sentence|/ComputeRelationshipSentence> with the entity
4521  names hyperlinked to the appropriate entity sections of the document.  names hyperlinked to the appropriate entity sections of the document.
# Line 2399  Line 4552 
4552          return $result;          return $result;
4553  }  }
4554    
4555  =head3 ShowRelationTable  =head3 _ShowRelationTable
4556    
4557  Generate the HTML string for a particular relation. The relation's data will be formatted as an HTML  Generate the HTML string for a particular relation. The relation's data will b