1 package DBIx::DBSchema;
4 use vars qw(@ISA $VERSION);
8 use FreezeThaw qw(freeze thaw cmpStr);
9 use DBIx::DBSchema::Table;
10 use DBIx::DBSchema::Column;
11 use DBIx::DBSchema::ColGroup::Unique;
12 use DBIx::DBSchema::ColGroup::Index;
21 DBIx::DBSchema - Database-independent schema objects
27 $schema = new DBIx::DBSchema @dbix_dbschema_table_objects;
28 $schema = new_odbc DBIx::DBSchema $dbh;
29 $schema = new_odbc DBIx::DBSchema $dsn, $user, $pass;
30 $schema = new_native DBIx::DBSchema $dbh;
31 $schema = new_native DBIx::DBSchema $dsn, $user, $pass;
33 $schema->save("filename");
34 $schema = load DBIx::DBSchema "filename";
36 $schema->addtable($dbix_dbschema_table_object);
38 @table_names = $schema->tables;
40 $DBIx_DBSchema_table_object = $schema->table("table_name");
42 @sql = $schema->sql($dbh);
43 @sql = $schema->sql($dsn, $username, $password);
44 @sql = $schema->sql($dsn); #doesn't connect to database - less reliable
46 $perl_code = $schema->pretty_print;
47 %hash = eval $perl_code;
48 use DBI qw(:sql_types); $schema = pretty_read DBIx::DBSchema \%hash;
52 DBIx::DBSchema objects are collections of DBIx::DBSchema::Table objects and
53 represent a database schema.
55 This module implements an OO-interface to database schemas. Using this module,
56 you can create a database schema with an OO Perl interface. You can read the
57 schema from an existing database. You can save the schema to disk and restore
58 it a different process. Most importantly, DBIx::DBSchema can write SQL
59 CREATE statements statements for different databases from a single source.
61 Currently supported databases are MySQL and PostgreSQL. Sybase support is
62 partially implemented. DBIx::DBSchema will attempt to use generic SQL syntax
63 for other databases. Assistance adding support for other databases is
64 welcomed. See L<DBIx::DBSchema::DBD>, "Driver Writer's Guide and Base Class".
70 =item new TABLE_OBJECT, TABLE_OBJECT, ...
72 Creates a new DBIx::DBSchema object.
77 my($proto, @tables) = @_;
78 my %tables = map { $_->name, $_ } @tables; #check for duplicates?
80 my $class = ref($proto) || $proto;
85 bless ($self, $class);
89 =item new_odbc DATABASE_HANDLE | DATA_SOURCE USERNAME PASSWORD [ ATTR ]
91 Creates a new DBIx::DBSchema object from an existing data source, which can be
92 specified by passing an open DBI database handle, or by passing the DBI data
93 source name, username, and password. This uses the experimental DBI type_info
94 method to create a schema with standard (ODBC) SQL column types that most
95 closely correspond to any non-portable column types. Use this to import a
96 schema that you wish to use with many different database engines. Although
97 primary key and (unique) index information will only be read from databases
98 with DBIx::DBSchema::DBD drivers (currently MySQL and PostgreSQL), import of
99 column names and attributes *should* work for any database. Note that this
100 method only uses "ODBC" column types; it does not require or use an ODBC
106 my($proto, $dbh) = (shift, shift);
107 $dbh = DBI->connect( $dbh, @_ ) or die $DBI::errstr unless ref($dbh);
109 map { new_odbc DBIx::DBSchema::Table $dbh, $_ } _tables_from_dbh($dbh)
113 =item new_native DATABASE_HANDLE | DATA_SOURCE USERNAME PASSWORD [ ATTR ]
115 Creates a new DBIx::DBSchema object from an existing data source, which can be
116 specified by passing an open DBI database handle, or by passing the DBI data
117 source name, username and password. This uses database-native methods to read
118 the schema, and will preserve any non-portable column types. The method is
119 only available if there is a DBIx::DBSchema::DBD for the corresponding database engine (currently, MySQL and PostgreSQL).
124 my($proto, $dbh) = (shift, shift);
125 $dbh = DBI->connect( $dbh, @_ ) or die $DBI::errstr unless ref($dbh);
127 map { new_native DBIx::DBSchema::Table ( $dbh, $_ ) } _tables_from_dbh($dbh)
133 Loads a DBIx::DBSchema object from a file.
138 my($proto,$file)=@_; #use $proto ?
139 open(FILE,"<$file") or die "Can't open $file: $!";
140 my($string)=join('',<FILE>); #can $string have newlines? pry not?
141 close FILE or die "Can't close $file: $!";
142 my($self)=thaw $string;
149 Saves a DBIx::DBSchema object to a file.
155 my($string)=freeze $self;
156 open(FILE,">$file") or die "Can't open $file: $!";
158 close FILE or die "Can't close file: $!";
159 my($check_self)=thaw $string;
160 die "Verify error: Can't freeze and thaw dbdef $self"
161 if (cmpStr($self,$check_self));
164 =item addtable TABLE_OBJECT
166 Adds the given DBIx::DBSchema::Table object to this DBIx::DBSchema.
172 $self->{'tables'}->{$table->name} = $table; #check for dupliates?
177 Returns a list of the names of all tables.
183 keys %{$self->{'tables'}};
186 =item table TABLENAME
188 Returns the specified DBIx::DBSchema::Table object.
194 $self->{'tables'}->{$table};
197 =item sql [ DATABASE_HANDLE | DATA_SOURCE [ USERNAME PASSWORD [ ATTR ] ] ]
199 Returns a list of SQL `CREATE' statements for this schema.
201 The data source can be specified by passing an open DBI database handle, or by
202 passing the DBI data source name, username and password.
204 Although the username and password are optional, it is best to call this method
205 with a database handle or data source including a valid username and password -
206 a DBI connection will be opened and the quoting and type mapping will be more
209 If passed a DBI data source (or handle) such as `DBI:mysql:database' or
210 `DBI:Pg:dbname=database', will use syntax specific to that database engine.
211 Currently supported databases are MySQL and PostgreSQL.
213 If not passed a data source (or handle), or if there is no driver for the
214 specified database, will attempt to use generic SQL syntax.
219 my($self, $dbh) = (shift, shift);
221 unless ( ref($dbh) || ! @_ ) {
222 $dbh = DBI->connect( $dbh, @_ ) or die $DBI::errstr;
225 my @r = map { $self->table($_)->sql_create_table($dbh); } $self->tables;
226 $dbh->disconnect if $created_dbh;
232 Returns the data in this schema as Perl source, suitable for assigning to a
245 #cant because -w complains about , in qw()
246 # (also biiiig problems with empty lengths)
248 #$self->table($table)->column($_)->type. " ".
249 #( $self->table($table)->column($_)->null ? 'NULL' : 0 ). " ".
250 #$self->table($table)->column($_)->length. " ),\n"
252 "'". $self->table($table)->column($_)->type. "', ".
253 "'". $self->table($table)->column($_)->null. "', ".
254 "'". $self->table($table)->column($_)->length. "', ".
255 "'". $self->table($table)->column($_)->default. "', ".
256 "'". $self->table($table)->column($_)->local. "',\n"
257 } $self->table($table)->columns
260 " 'primary_key' => '". $self->table($table)->primary_key. "',\n".
261 " 'unique' => [ ". join(', ',
262 map { "[ '". join("', '", @{$_}). "' ]" }
263 @{$self->table($table)->unique->lol_ref}
265 " 'index' => [ ". join(', ',
266 map { "[ '". join("', '", @{$_}). "' ]" }
267 @{$self->table($table)->index->lol_ref}
269 #" 'index' => [ ". " ],\n"
276 =item pretty_read HASHREF
278 Creates a schema as specified by a data structure such as that created by
279 B<pretty_print> method.
284 my($proto, $href) = @_;
285 my $schema = $proto->new( map {
287 while ( @{$href->{$_}{'columns'}} ) {
288 push @columns, DBIx::DBSchema::Column->new(
289 splice @{$href->{$_}{'columns'}}, 0, 6
292 DBIx::DBSchema::Table->new(
294 $href->{$_}{'primary_key'},
295 DBIx::DBSchema::ColGroup::Unique->new($href->{$_}{'unique'}),
296 DBIx::DBSchema::ColGroup::Index->new($href->{$_}{'index'}),
302 # private subroutines
308 $driver = $dbh->{Driver}->{Name};
310 $dbh =~ s/^dbi:(\w*?)(?:\((.*?)\))?://i #nicked from DBI->connect
311 or '' =~ /()/; # ensure $1 etc are empty if match fails
312 $driver = $1 or confess "can't parse data source: $dbh";
315 #require "DBIx/DBSchema/DBD/$driver.pm";
317 eval 'require "DBIx/DBSchema/DBD/$driver.pm"' and $driver or die $@;
320 sub _tables_from_dbh {
322 my $sth = $dbh->table_info or die $dbh->errstr;
323 #map { $_->{TABLE_NAME} } grep { $_->{TABLE_TYPE} eq 'TABLE' }
324 # @{ $sth->fetchall_arrayref({ TABLE_NAME=>1, TABLE_TYPE=>1}) };
325 map { $_->[0] } grep { $_->[1] =~ /^TABLE$/i }
326 @{ $sth->fetchall_arrayref([2,3]) };
333 Ivan Kohler <ivan-dbix-dbschema@420.am>
335 Charles Shapiro <charles.shapiro@numethods.com> and Mitchell Friedman
336 <mitchell.friedman@numethods.com> contributed the start of a Sybase driver.
340 Copyright (c) 2000 Ivan Kohler
341 Copyright (c) 2000 Mail Abuse Prevention System LLC
343 This program is free software; you can redistribute it and/or modify it under
344 the same terms as Perl itself.
348 Each DBIx::DBSchema object should have a name which corresponds to its name
349 within the SQL database engine (DBI data source).
351 pretty_print is actually pretty ugly.
353 Perhaps pretty_read should eval column types so that we can use DBI
354 qw(:sql_types) here instead of externally.
358 L<DBIx::DBSchema::Table>, L<DBIx::DBSchema::ColGroup>,
359 L<DBIx::DBSchema::ColGroup::Unique>, L<DBIx::DBSchema::ColGroup::Index>,
360 L<DBIx::DBSchema::Column>, L<DBIx::DBSchema::DBD>,
361 L<DBIx::DBSchema::DBD::mysql>, L<DBIx::DBSchema::DBD::Pg>, L<FS::Record>,