1 package DBIx::DBSchema;
4 use vars qw($VERSION $DEBUG $errstr);
6 use DBIx::DBSchema::_util qw(_load_driver _dbh _parse_opt);
7 use DBIx::DBSchema::Table 0.05;
8 use DBIx::DBSchema::Index;
9 use DBIx::DBSchema::Column;
10 use DBIx::DBSchema::ColGroup::Unique;
11 use DBIx::DBSchema::ColGroup::Index;
14 $VERSION = eval $VERSION; # modperlstyle: convert the string into a number
20 DBIx::DBSchema - Database-independent schema objects
26 $schema = new DBIx::DBSchema @dbix_dbschema_table_objects;
27 $schema = new_odbc DBIx::DBSchema $dbh;
28 $schema = new_odbc DBIx::DBSchema $dsn, $user, $pass;
29 $schema = new_native DBIx::DBSchema $dbh;
30 $schema = new_native DBIx::DBSchema $dsn, $user, $pass;
32 $schema->save("filename");
33 $schema = load DBIx::DBSchema "filename" or die $DBIx::DBSchema::errstr;
35 $schema->addtable($dbix_dbschema_table_object);
37 @table_names = $schema->tables;
39 $DBIx_DBSchema_table_object = $schema->table("table_name");
41 @sql = $schema->sql($dbh);
42 @sql = $schema->sql($dsn, $username, $password);
43 @sql = $schema->sql($dsn); #doesn't connect to database - less reliable
45 $perl_code = $schema->pretty_print;
46 %hash = eval $perl_code;
47 use DBI qw(:sql_types); $schema = pretty_read DBIx::DBSchema \%hash;
51 DBIx::DBSchema objects are collections of DBIx::DBSchema::Table objects and
52 represent a database schema.
54 This module implements an OO-interface to database schemas. Using this module,
55 you can create a database schema with an OO Perl interface. You can read the
56 schema from an existing database. You can save the schema to disk and restore
57 it in a different process. You can write SQL CREATE statements statements for
58 different databases from a single source. In recent versions, you can
59 transform one schema to another, adding any necessary new columns and tables
60 (and, as of 0.33, indices).
62 Currently supported databases are MySQL, PostgreSQL and SQLite. Sybase and
63 Oracle drivers are partially implemented. DBIx::DBSchema will attempt to use
64 generic SQL syntax for other databases. Assistance adding support for other
65 databases is welcomed. See L<DBIx::DBSchema::DBD>, "Driver Writer's Guide and
72 =item new TABLE_OBJECT, TABLE_OBJECT, ...
74 Creates a new DBIx::DBSchema object.
79 my($proto, @tables) = @_;
80 my %tables = map { $_->name, $_ } @tables; #check for duplicates?
82 my $class = ref($proto) || $proto;
87 bless ($self, $class);
91 =item new_odbc DATABASE_HANDLE | DATA_SOURCE USERNAME PASSWORD [ ATTR ]
93 Creates a new DBIx::DBSchema object from an existing data source, which can be
94 specified by passing an open DBI database handle, or by passing the DBI data
95 source name, username, and password. This uses the experimental DBI type_info
96 method to create a schema with standard (ODBC) SQL column types that most
97 closely correspond to any non-portable column types. Use this to import a
98 schema that you wish to use with many different database engines. Although
99 primary key and (unique) index information will only be read from databases
100 with DBIx::DBSchema::DBD drivers (currently MySQL and PostgreSQL), import of
101 column names and attributes *should* work for any database. Note that this
102 method only uses "ODBC" column types; it does not require or use an ODBC
108 my($proto, $dbh) = ( shift, _dbh(@_) );
110 map { new_odbc DBIx::DBSchema::Table $dbh, $_ } _tables_from_dbh($dbh)
114 =item new_native DATABASE_HANDLE | DATA_SOURCE USERNAME PASSWORD [ ATTR ]
116 Creates a new DBIx::DBSchema object from an existing data source, which can be
117 specified by passing an open DBI database handle, or by passing the DBI data
118 source name, username and password. This uses database-native methods to read
119 the schema, and will preserve any non-portable column types. The method is
120 only available if there is a DBIx::DBSchema::DBD for the corresponding database engine (currently, MySQL and PostgreSQL).
125 my($proto, $dbh) = (shift, _dbh(@_) );
127 map { new_native DBIx::DBSchema::Table ( $dbh, $_ ) } _tables_from_dbh($dbh)
133 Loads a DBIx::DBSchema object from a file. If there is an error, returns
134 false and puts an error message in $DBIx::DBSchema::errstr;
139 my($proto,$file)=@_; #use $proto ?
144 eval { $self = Storable::retrieve($file); };
146 if ( $@ && $@ =~ /not.*storable/i ) { #then try FreezeThaw
149 eval "use FreezeThaw;";
154 or do { $errstr = "Can't open $file: $!"; return ''; };
155 my $string = join('',<FILE>);
157 or do { $errstr = "Can't close $file: $!"; return ''; };
158 ($self) = FreezeThaw::thaw($string);
172 Saves a DBIx::DBSchema object to a file.
177 #my($self, $file) = @_;
178 Storable::nstore(@_);
181 =item addtable TABLE_OBJECT
183 Adds the given DBIx::DBSchema::Table object to this DBIx::DBSchema.
189 $self->{'tables'}->{$table->name} = $table; #check for dupliates?
194 Returns a list of the names of all tables.
200 keys %{$self->{'tables'}};
203 =item table TABLENAME
205 Returns the specified DBIx::DBSchema::Table object.
211 $self->{'tables'}->{$table};
214 =item sql [ DATABASE_HANDLE | DATA_SOURCE [ USERNAME PASSWORD [ ATTR ] ] ]
216 Returns a list of SQL `CREATE' statements for this schema.
218 The data source can be specified by passing an open DBI database handle, or by
219 passing the DBI data source name, username and password.
221 Although the username and password are optional, it is best to call this method
222 with a database handle or data source including a valid username and password -
223 a DBI connection will be opened and used to check the database version as well
224 as for more reliable quoting and type mapping. Note that the database
225 connection will be used passively, B<not> to actually run the CREATE
228 If passed a DBI data source (or handle) such as `DBI:mysql:database' or
229 `DBI:Pg:dbname=database', will use syntax specific to that database engine.
230 Currently supported databases are MySQL and PostgreSQL.
232 If not passed a data source (or handle), or if there is no driver for the
233 specified database, will attempt to use generic SQL syntax.
238 my($self, $dbh) = ( shift, _dbh(@_) );
239 map { $self->table($_)->sql_create_table($dbh); } $self->tables;
242 =item sql_update_schema [ OPTIONS_HASHREF, ] PROTOTYPE_SCHEMA [ DATABASE_HANDLE | DATA_SOURCE [ USERNAME PASSWORD [ ATTR ] ] ]
244 Returns a list of SQL statements to update this schema so that it is idential
245 to the provided prototype schema, also a DBIx::DBSchema object.
247 Right now this method knows how to add new tables and alter existing tables,
248 including indices. If specifically requested by passing an options hashref
249 with B<drop_tables> set true before all other arguments, it will also drop
252 See L<DBIx::DBSchema::Table/sql_alter_table>,
253 L<DBIx::DBSchema::Column/sql_add_coumn> and
254 L<DBIx::DBSchema::Column/sql_alter_column> for additional specifics and
257 The data source can be specified by passing an open DBI database handle, or by
258 passing the DBI data source name, username and password.
260 Although the username and password are optional, it is best to call this method
261 with a database handle or data source including a valid username and password -
262 a DBI connection will be opened and used to check the database version as well
263 as for more reliable quoting and type mapping. Note that the database
264 connection will be used passively, B<not> to actually run the CREATE
267 If passed a DBI data source (or handle) such as `DBI:mysql:database' or
268 `DBI:Pg:dbname=database', will use syntax specific to that database engine.
269 Currently supported databases are MySQL and PostgreSQL.
271 If not passed a data source (or handle), or if there is no driver for the
272 specified database, will attempt to use generic SQL syntax.
276 #gosh, false laziness w/DBSchema::Table::sql_alter_schema
278 sub sql_update_schema {
279 #my($self, $new, $dbh) = ( shift, shift, _dbh(@_) );
280 my($self, $opt, $new, $dbh) = ( shift, _parse_opt(\@_), shift, _dbh(@_) );
284 foreach my $table ( $new->tables ) {
286 if ( $self->table($table) ) {
288 warn "$table exists\n" if $DEBUG > 1;
291 $self->table($table)->sql_alter_table( $new->table($table), $dbh );
295 warn "table $table does not exist.\n" if $DEBUG;
298 $new->table($table)->sql_create_table( $dbh );
304 if ( $opt->{'drop_tables'} ) {
306 warn "drop_tables enabled\n" if $DEBUG;
308 # drop tables not in $new
309 foreach my $table ( grep !$new->table($_), $self->tables ) {
311 warn "table $table should be dropped.\n" if $DEBUG;
313 push @r, $self->table($table)->sql_drop_table( $dbh );
319 warn join("\n", @r). "\n"
326 =item update_schema [ OPTIONS_HASHREF, ] PROTOTYPE_SCHEMA, DATABASE_HANDLE | DATA_SOURCE [ USERNAME PASSWORD [ ATTR ] ]
328 Same as sql_update_schema, except actually runs the SQL commands to update
329 the schema. Throws a fatal error if any statement fails.
334 #my($self, $new, $dbh) = ( shift, shift, _dbh(@_) );
335 my($self, $opt, $new, $dbh) = ( shift, _parse_opt(\@_), shift, _dbh(@_) );
337 foreach my $statement ( $self->sql_update_schema( $opt, $new, $dbh ) ) {
338 $dbh->do( $statement )
339 or die "Error: ". $dbh->errstr. "\n executing: $statement";
346 Returns the data in this schema as Perl source, suitable for assigning to a
357 my $table = $self->table($tablename);
358 my %indices = $table->indices;
360 "'$tablename' => {\n".
363 #cant because -w complains about , in qw()
364 # (also biiiig problems with empty lengths)
366 #$table->column($_)->type. " ".
367 #( $table->column($_)->null ? 'NULL' : 0 ). " ".
368 #$table->column($_)->length. " ),\n"
370 "'". $table->column($_)->type. "', ".
371 "'". $table->column($_)->null. "', ".
372 "'". $table->column($_)->length. "', ".
373 "'". $table->column($_)->default. "', ".
374 "'". $table->column($_)->local. "',\n"
378 " 'primary_key' => '". $table->primary_key. "',\n".
380 #old style index representation..
383 $table->{'unique'} # $table->_unique
384 ? " 'unique' => [ ". join(', ',
385 map { "[ '". join("', '", @{$_}). "' ]" }
386 @{$table->_unique->lol_ref}
391 ( $table->{'index'} # $table->_index
392 ? " 'index' => [ ". join(', ',
393 map { "[ '". join("', '", @{$_}). "' ]" }
394 @{$table->_index->lol_ref}
400 " 'indices' => { ". join( ",\n ",
402 map { my $iname = $_;
403 my $index = $indices{$iname};
406 ? " 'using' => '". $index->using ."',\n"
409 " 'unique' => ". $index->_unique .",\n".
411 join("', '", @{$index->columns} ).
425 =item pretty_read HASHREF
427 Creates a schema as specified by a data structure such as that created by
428 B<pretty_print> method.
433 my($proto, $href) = @_;
435 my $schema = $proto->new( map {
438 my $info = $href->{$tablename};
441 while ( @{$info->{'columns'}} ) {
442 push @columns, DBIx::DBSchema::Column->new(
443 splice @{$info->{'columns'}}, 0, 6
447 DBIx::DBSchema::Table->new({
448 'name' => $tablename,
449 'primary_key' => $info->{'primary_key'},
450 'columns' => \@columns,
453 'unique' => DBIx::DBSchema::ColGroup::Unique->new($info->{'unique'}),
454 'index' => DBIx::DBSchema::ColGroup::Index->new($info->{'index'}),
457 'indices' => [ map { my $idx_info = $info->{'indices'}{$_};
458 DBIx::DBSchema::Index->new({
461 'unique' => $idx_info->{'unique'},
462 'columns' => $idx_info->{'columns'},
465 keys %{ $info->{'indices'} }
473 # private subroutines
475 sub _tables_from_dbh {
477 my $driver = _load_driver($dbh);
479 scalar(eval "DBIx::DBSchema::DBD::$driver->default_db_catalog");
481 scalar(eval "DBIx::DBSchema::DBD::$driver->default_db_schema");
482 my $sth = $dbh->table_info($db_catalog, $db_schema, '', 'TABLE')
484 #map { $_->{TABLE_NAME} } grep { $_->{TABLE_TYPE} eq 'TABLE' }
485 # @{ $sth->fetchall_arrayref({ TABLE_NAME=>1, TABLE_TYPE=>1}) };
486 map { $_->[0] } grep { $_->[1] =~ /^TABLE$/i }
487 @{ $sth->fetchall_arrayref([2,3]) };
494 Ivan Kohler <ivan-dbix-dbschema@420.am>
496 Charles Shapiro <charles.shapiro@numethods.com> and Mitchell Friedman
497 <mitchell.friedman@numethods.com> contributed the start of a Sybase driver.
499 Daniel Hanks <hanksdc@about-inc.com> contributed the Oracle driver.
501 Jesse Vincent contributed the SQLite driver and fixes to quiet down
502 internal usage of the old API.
504 Slaven Rezic <srezic@cpan.org> contributed column and table dropping, Pg
509 Contributions are welcome! I'm especially keen on any interest in the top
510 items/projects below under BUGS.
514 Copyright (c) 2000-2007 Ivan Kohler
515 Copyright (c) 2000 Mail Abuse Prevention System LLC
516 Copyright (c) 2007 Freeside Internet Services, Inc.
518 This program is free software; you can redistribute it and/or modify it under
519 the same terms as Perl itself.
523 Multiple primary keys are not yet supported.
525 Foreign keys and other constraints are not yet supported.
527 Eventually it would be nice to have additional transformations (deleted,
528 modified columns). sql_update_schema doesn't deal with deleted or modified
531 Need to port and test with additional databases
533 Each DBIx::DBSchema object should have a name which corresponds to its name
534 within the SQL database engine (DBI data source).
536 pretty_print is actually pretty ugly.
538 pretty_print isn't so good about quoting values... save/load is a much better
539 alternative to using pretty_print/pretty_read
541 pretty_read is pretty ugly too.
543 pretty_read should *not* create and pass in old-style unique/index indices
544 when nothing is given in the read.
546 Perhaps pretty_read should eval column types so that we can use DBI
547 qw(:sql_types) here instead of externally.
549 Need to support "using" index attribute in pretty_read and in reverse
552 perhaps we should just get rid of pretty_read entirely. pretty_print is useful
553 for debugging, but pretty_read is pretty bunk.
555 sql CREATE TABLE output should convert integers
556 (i.e. use DBI qw(:sql_types);) to local types using DBI->type_info plus a hash
561 L<DBIx::DBSchema::Table>, L<DBIx::DBSchema::Index>,
562 L<DBIx::DBSchema::Column>, L<DBIx::DBSchema::DBD>,
563 L<DBIx::DBSchema::DBD::mysql>, L<DBIx::DBSchema::DBD::Pg>, L<FS::Record>,