1 package SQL::Translator::Schema;
3 # ----------------------------------------------------------------------
4 # $Id: Schema.pm,v 1.6 2003-06-09 04:18:23 kycl4rk Exp $
5 # ----------------------------------------------------------------------
6 # Copyright (C) 2003 Ken Y. Clark <kclark@cpan.org>
8 # This program is free software; you can redistribute it and/or
9 # modify it under the terms of the GNU General Public License as
10 # published by the Free Software Foundation; version 2.
12 # This program is distributed in the hope that it will be useful, but
13 # WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 # General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program; if not, write to the Free Software
19 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
21 # -------------------------------------------------------------------
27 SQL::Translator::Schema - SQL::Translator schema object
31 use SQL::Translator::Schema;
32 my $schema = SQL::Translator::Schema->new;
33 my $table = $schema->add_table( name => 'foo' );
34 my $view = $schema->add_view( name => 'bar', sql => '...' );
38 C<SQL::Translator::Schema> is the object that accepts, validates, and
39 returns the database structure.
47 use SQL::Translator::Schema::Constants;
48 use SQL::Translator::Schema::Table;
49 use SQL::Translator::Schema::View;
51 use base 'Class::Base';
52 use vars qw[ $VERSION $TABLE_ORDER $VIEW_ORDER ];
56 # ----------------------------------------------------------------------
65 my $schema = SQL::Translator->new(
72 my ( $self, $config ) = @_;
73 $self->params( $config, qw[ name database ] ) || return undef;
77 # ----------------------------------------------------------------------
84 Add a table object. Returns the new SQL::Translator::Schema::Table object.
85 The "name" parameter is required. If you try to create a table with the
86 same name as an existing table, you will get an error and the table will
89 my $t1 = $schema->add_table( name => 'foo' ) or die $schema->error;
90 my $t2 = SQL::Translator::Schema::Table->new( name => 'bar' );
91 $t2 = $schema->add_table( $table_bar ) or die $schema->error;
96 my $table_class = 'SQL::Translator::Schema::Table';
99 if ( UNIVERSAL::isa( $_[0], $table_class ) ) {
101 $table->schema( $self );
105 $args{'schema'} = $self;
106 $table = $table_class->new( \%args ) or return
107 $self->error( $table_class->error );
110 $table->order( ++$TABLE_ORDER );
111 my $table_name = $table->name or return $self->error('No table name');
113 if ( defined $self->{'tables'}{ $table_name } ) {
114 return $self->error(qq[Can't create table: "$table_name" exists]);
117 $self->{'tables'}{ $table_name } = $table;
123 # ----------------------------------------------------------------------
130 Add a view object. Returns the new SQL::Translator::Schema::View object.
131 The "name" parameter is required. If you try to create a view with the
132 same name as an existing view, you will get an error and the view will
135 my $v1 = $schema->add_view( name => 'foo' );
136 my $v2 = SQL::Translator::Schema::View->new( name => 'bar' );
137 $v2 = $schema->add_view( $view_bar ) or die $schema->error;
142 my $view_class = 'SQL::Translator::Schema::View';
145 if ( UNIVERSAL::isa( $_[0], $view_class ) ) {
150 return $self->error('No view name') unless $args{'name'};
151 $view = $view_class->new( \%args ) or return $view_class->error;
154 $view->order( ++$VIEW_ORDER );
155 my $view_name = $view->name or return $self->error('No view name');
157 if ( defined $self->{'views'}{ $view_name } ) {
158 return $self->error(qq[Can't create view: "$view_name" exists]);
161 $self->{'views'}{ $view_name } = $view;
167 # ----------------------------------------------------------------------
174 Get or set the schema's database. (optional)
176 my $database = $schema->database('PostgreSQL');
181 $self->{'database'} = shift if @_;
182 return $self->{'database'} || '';
185 # ----------------------------------------------------------------------
192 Returns true if all the tables and views are valid.
194 my $ok = $schema->is_valid or die $schema->error;
200 return $self->error('No tables') unless $self->get_tables;
202 for my $object ( $self->get_tables, $self->get_views ) {
203 return $object->error unless $object->is_valid;
209 # ----------------------------------------------------------------------
216 Returns a table by the name provided.
218 my $table = $schema->get_table('foo');
223 my $table_name = shift or return $self->error('No table name');
224 return $self->error( qq[Table "$table_name" does not exist] ) unless
225 exists $self->{'tables'}{ $table_name };
226 return $self->{'tables'}{ $table_name };
229 # ----------------------------------------------------------------------
236 Returns all the tables as an array or array reference.
238 my @tables = $schema->get_tables;
245 sort { $a->[0] <=> $b->[0] }
246 map { [ $_->order, $_ ] }
247 values %{ $self->{'tables'} };
250 return wantarray ? @tables : \@tables;
253 $self->error('No tables');
254 return wantarray ? () : undef;
258 # ----------------------------------------------------------------------
265 Returns a view by the name provided.
267 my $view = $schema->get_view('foo');
272 my $view_name = shift or return $self->error('No view name');
273 return $self->error('View "$view_name" does not exist') unless
274 exists $self->{'views'}{ $view_name };
275 return $self->{'views'}{ $view_name };
278 # ----------------------------------------------------------------------
285 Returns all the views as an array or array reference.
287 my @views = $schema->get_views;
294 sort { $a->[0] <=> $b->[0] }
295 map { [ $_->order, $_ ] }
296 values %{ $self->{'views'} };
299 return wantarray ? @views : \@views;
302 $self->error('No views');
303 return wantarray ? () : undef;
307 # ----------------------------------------------------------------------
308 sub make_natural_joins {
312 =head2 make_natural_joins
314 Creates foriegn key relationships among like-named fields in different
315 tables. Accepts the following arguments:
321 A True or False argument which determins whether or not to perform
322 the joins from primary keys to fields of the same name in other tables
326 A list of fields to skip in the joins
330 $schema->make_natural_joins(
332 skip_fields => 'name,department_id',
339 my $join_pk_only = $args{'join_pk_only'} || 0;
340 my %skip_fields = map { $_, 1 } @{ parse_list_arg($args{'skip_fields'}) };
342 my ( %common_keys, %pk );
343 for my $table ( $self->get_tables ) {
344 for my $field ( $table->get_fields ) {
345 my $field_name = $field->name or next;
346 next if $skip_fields{ $field_name };
347 $pk{ $field_name } = 1 if $field->is_primary_key;
348 push @{ $common_keys{ $field_name } }, $table->name;
352 for my $field ( keys %common_keys ) {
353 next if $join_pk_only and !defined $pk{ $field };
355 my @table_names = @{ $common_keys{ $field } };
356 next unless scalar @table_names > 1;
358 for my $i ( 0 .. $#table_names ) {
359 my $table1 = $self->get_table( $table_names[ $i ] ) or next;
361 for my $j ( 1 .. $#table_names ) {
362 my $table2 = $self->get_table( $table_names[ $j ] ) or next;
363 next if $table1->name eq $table2->name;
365 $table1->add_constraint(
368 reference_table => $table2->name,
369 reference_fields => $field,
378 # ----------------------------------------------------------------------
385 Get or set the schema's name. (optional)
387 my $schema_name = $schema->name('Foo Database');
392 $self->{'name'} = shift if @_;
393 return $self->{'name'} || '';
396 # ----------------------------------------------------------------------
399 undef $_ for values %{ $self->{'tables'} };
400 undef $_ for values %{ $self->{'views'} };
405 # ----------------------------------------------------------------------
411 Ken Y. Clark E<lt>kclark@cpan.orgE<gt>