NAME

Jifty::DBI::SchemaGenerator - Generate a table schema from Jifty::DBI records

DESCRIPTION

This module turns a Jifty::Record object into an SQL schema for your chosen database. At the moment, your choices are MySQL, SQLite, or PostgreSQL. Oracle might also work right, though it's untested.

SYNOPSIS

The Short Answer

See below for where we get the $handle and $model variables.

  use Jifty::DBI::SchemaGenerator;
  ...
  my $s_gen = Jifty::DBI::SchemaGenerator->new( $handle );
  $s_gen->add_model($model);

  my @statements = $s_gen->create_table_sql_statements;
  print join("\n", @statements, '');
  ...

The Long Version

See Jifty::DBI for details about the first two parts.

MyModel

  package MyModel; 
  # lib/MyModel.pm

  use warnings;
  use strict;

  use base qw(Jifty::DBI::Record);
  # your custom code goes here.
  1;

MyModel::Schema

  package MyModel::Schema;
  # lib/MyModel/Schema.pm

  use warnings;
  use strict;

  use Jifty::DBI::Schema;

  column foo => type is 'text';
  column bar => type is 'text';

  1;

myscript.pl

  #!/usr/bin/env perl
  # myscript.pl

  use strict;
  use warnings;

  use Jifty::DBI::SchemaGenerator;

  use Jifty::DBI::Handle;
  use MyModel;
  use MyModel::Schema;

  my $handle = Jifty::DBI::Handle->new();
  $handle->connect(
    driver   => 'SQLite',
    database => 'testdb',
  );

  my $model = MyModel->new($handle);
  my $s_gen = Jifty::DBI::SchemaGenerator->new( $handle );
  $s_gen->add_model($model);

  # here's the basic point of this module:
  my @statements = $s_gen->create_table_sql_statements;
  print join("\n", @statements, '');

  # this part is directly from Jifty::Script::Schema::create_all_tables()
  $handle->begin_transaction;
  for my $statement (@statements) {
    my $ret = $handle->simple_query($statement);
    $ret or die "error creating a table: " . $ret->error_message;
  }
  $handle->commit;

CONFIGURATION AND ENVIRONMENT

Requires no configuration files or environment variables.

DEPENDENCIES

Class::Accessor::Fast

DBIx::DBSchema

Class::ReturnValue

METHODS

new HANDLE

Creates a new "Jifty::DBI::SchemaGenerator" object. The single required argument is a "Jifty::DBI::Handle".

Adds a new model class to the SchemaGenerator. Model should be an object which is an instance of "Jifty::DBI::Record" or a subclass thereof. It may also be a string which is the name of such a class/subclass; in the latter case, "add_model" will instantiate an object of the class.

The model must define the instance methods "schema" and "table".

Returns true if the model was added successfully; returns a false "Class::ReturnValue" error otherwise.

column_definition_sql TABLENAME COLUMNNAME

Given a table name and a column name, returns the SQL fragment describing that column for the current database.

create_table_sql_statements

Returns a list of SQL statements (as strings) to create tables for all of the models added to the SchemaGenerator.

create_table_sql_text

Returns a string containing a sequence of SQL statements to create tables for all of the models added to the SchemaGenerator.

This is just a trivial wrapper around "create_table_sql_statements".

PRIVATE _db_schema_table_from_model MODEL

Takes an object of a subclass of Jifty::DBI::Record; returns a new "DBIx::DBSchema::Table" object corresponding to the model.

PRIVATE _error STRING

Takes in a string and returns it as a Class::ReturnValue error object.

INCOMPATIBILITIES

None reported.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to "bug-<RT NAME>@rt.cpan.org", or through the web interface at <http://rt.cpan.org>.

AUTHOR

David Glasser "glasser@bestpractical.com"

Some pod by Eric Wilhelm <ewilhelm at cpan dot org>

LICENCE AND COPYRIGHT

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.

DISCLAIMER OF WARRANTY

BECAUSE THIS SOFTWARE IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR THE SOFTWARE, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE SOFTWARE "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE SOFTWARE IS WITH YOU. SHOULD THE SOFTWARE PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR, OR CORRECTION.

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