Make a DBIC Schema from DDL

For some reason, creating DBIx::Class schemas by hand has never made sense to me. I like to write my CREATE TABLE statements instead. DBIx::Class::Schema::Loader works really well for this.

I keep this schema DDL in version control. I also keep a SQLite database around with some test data (but the database isn't in version control).

I usually find myself writing a little shell script or other program to to regenerate the DBIC schema from that test database. That usually requires me to make manual changes to the test database representing the changes I've just made to the DDL.

After doing this one too many times, I decided to combine DBIx::RunSQL with the schema loader. By creating a SQLite database from my DDL in memory, I can create a schema without me modifying any databases manually.

This was easier than I thought:

#!/usr/bin/env perl

use Modern::Perl;

use DBIx::RunSQL;
use DBIx::Class::Schema::Loader 'make_schema_at';

my $test_dbh = DBIx::RunSQL->create(
    dsn     => 'dbi:SQLite:dbname=:memory:',
    sql     => 'db/schema.sql',
    force   => 1,
    verbose => 1,

make_schema_at( 'MyApp::Schema',
        components => [ 'InflateColumn::DateTime', 'TimeStamp' ],
        debug => 1,
        dump_directory => './lib' ,
    [ sub { $test_dbh }, {} ]

The next step is to connect everything to DBIx::Class::Migration—but first things first.

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About this Entry

This page contains a single entry by chromatic published on April 27, 2012 1:05 PM.

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