DBIx::C...::Loader(3)

🦋 DBIx::Class::Schema::Loader(3) — manual page, bestie 🦋

okay so this is the DBIx::Class::Schema::Loader(3) page from User Contributed Perl Documentation, and we are gonna make it make sense. It is a Perl module thingie, and the whole vibe is: it builds a DBIx::Class::Schema by looking at your actual database and setting up the classes for you. iconic behavior, honestly 💅

✨ NAME ✨

DBIx::Class::Schema::Loader — create a DBIx::Class::Schema based on a database.

🌈 SYNOPSIS 🌈

bestie, here is the whole “show me how it looks” section. The code is exactly the code, no cap:

    ### use this module to generate a set of class files

    # in a script
    use DBIx::Class::Schema::Loader qw/ make_schema_at /;
    make_schema_at(
        'My::Schema',
        { debug => 1,
          dump_directory => './lib',
        },
        [ 'dbi:Pg:dbname="foo"', 'myuser', 'mypassword',
           { loader_class => 'MyLoader' } # optionally
        ],
    );

    # from the command line or a shell script with dbicdump (distributed
    # with this module).  Do `perldoc dbicdump` for usage.
    dbicdump -o dump_directory=./lib \
             -o components='["InflateColumn::DateTime"]' \
             -o debug=1 \
             My::Schema \
             'dbi:Pg:dbname=foo' \
             myuser \
             mypassword

    ### or generate and load classes at runtime
    # note: this technique is not recommended
    # for use in production code

    package My::Schema;
    use base qw/DBIx::Class::Schema::Loader/;

    __PACKAGE__->loader_options(
        constraint              => '^foo.*',
        # debug                 => 1,
    );

    #### in application code elsewhere:

    use My::Schema;

    my $schema1 = My::Schema->connect( $dsn, $user, $password, $attrs);
    # -or-
    my $schema1 = "My::Schema"; $schema1->connection(as above);

💖 DESCRIPTION 💖

DBIx::Class::Schema::Loader automates the definition of a DBIx::Class::Schema by scanning database table definitions and setting up the columns, primary keys, unique constraints and relationships. literally the whole point ✨

See dbicdump for the dbicdump utility.

DBIx::Class::Schema::Loader currently supports only the DBI storage type. It has explicit support for DBD::Pg, DBD::mysql, DBD::DB2, DBD::Firebird, DBD::InterBase, DBD::Informix, DBD::SQLAnywhere, DBD::SQLite, DBD::Sybase (for Sybase ASE and MSSSQL), DBD::ODBC (for MSSQL, MSAccess, Firebird and SQL Anywhere) DBD::ADO (for MSSQL and MSAccess) and DBD::Oracle. Other DBI drivers may function to a greater or lesser degree with this loader, depending on how much of the DBI spec they implement, and how standard their implementation is.

Patches to make other DBDs work correctly welcome.

See DBIx::Class::Schema::Loader::DBI::Writing for notes on writing your own vendor-specific subclass for an unsupported DBD driver.

This module requires DBIx::Class 0.08127 or later, and obsoletes the older DBIx::Class::Loader.

See DBIx::Class::Schema::Loader::Base for available options.

🧚 METHODS 🧚

🧸 loader

The loader object, as class data on your Schema. For methods available see DBIx::Class::Schema::Loader::Base and DBIx::Class::Schema::Loader::DBI. it’s giving “the actual brain cell of the operation” 🧠✨

🏷️ loader_class

• Argument: $loader_class

Set the loader class to be instantiated when connection is called. If the classname starts with ::, DBIx::Class::Schema::Loader is prepended. Defaults to storage_type in DBIx::Class::Schema (which must start with :: when using DBIx::Class::Schema::Loader).

This is mostly useful for subclassing existing loaders or in conjunction with dump_to_dir.

🎀 loader_options

• Argument: \%loader_options

Example in Synopsis above demonstrates a few common arguments. For detailed information on all of the arguments, most of which are only useful in fairly complex scenarios, see the DBIx::Class::Schema::Loader::Base documentation.

bestie, listen: if you intend to use loader_options, you must call loader_options before any connection is made, or embed the loader_options in the connection information itself as shown below. Setting loader_options after the connection has already been made is useless. like, genuinely useless, no cap 💀

🔌 connection

• Arguments: @args
• Return Value: $new_schema

See connection in DBIx::Class::Schema for basic usage.

If the final argument is a hashref, and it contains the keys loader_options or loader_class, those keys will be deleted, and their values value will be used for the loader options or class, respectively, just as if set via the loader_options or loader_class methods above.

The actual auto-loading operation (the heart of this module) will be invoked as soon as the connection information is defined. main character energy 👑

🐚 clone

See clone in DBIx::Class::Schema.

📁 dump_to_dir

• Argument: $directory

Calling this as a class method on either DBIx::Class::Schema::Loader or any derived schema class will cause all schemas to dump manual versions of themselves to the named directory when they are loaded. In order to be effective, this must be set before defining a connection on this schema class or any derived object (as the loading happens as soon as both a connection and loader_options are set, and only once per class).

See dump_directory in DBIx::Class::Schema::Loader::Base for more details on the dumping mechanism.

This can also be set at module import time via the import option dump_to_dir:/foo/bar to DBIx::Class::Schema::Loader, where /foo/bar is the target directory.

Examples:

    # My::Schema isa DBIx::Class::Schema::Loader, and has connection info
    #   hardcoded in the class itself:
    perl -MDBIx::Class::Schema::Loader=dump_to_dir:/foo/bar -MMy::Schema -e1

    # Same, but no hard-coded connection, so we must provide one:
    perl -MDBIx::Class::Schema::Loader=dump_to_dir:/foo/bar -MMy::Schema -e 'My::Schema->connection("dbi:Pg:dbname=foo", ...)'

    # Or as a class method, as long as you get it done *before* defining a
    #  connection on this schema class or any derived object:
    use My::Schema;
    My::Schema->dump_to_dir('/foo/bar');
    My::Schema->connection(........);

    # Or as a class method on the DBIx::Class::Schema::Loader itself, which affects all
    #   derived schemas
    use My::Schema;
    use My::OtherSchema;
    DBIx::Class::Schema::Loader->dump_to_dir('/foo/bar');
    My::Schema->connection(.......);
    My::OtherSchema->connection(.......);

    # Another alternative to the above:
    use DBIx::Class::Schema::Loader qw| dump_to_dir:/foo/bar |;
    use My::Schema;
    use My::OtherSchema;
    My::Schema->connection(.......);
    My::OtherSchema->connection(.......);

🪄 make_schema_at

• Arguments: $schema_class_name, \%loader_options, \@connect_info
• Return Value: $schema_class_name

This function creates a DBIx::Class schema from an existing RDBMS schema. With the dump_directory option, generates a set of DBIx::Class classes from an existing database schema read from the given dsn. Without a dump_directory, creates schema classes in memory at runtime without generating on-disk class files.

For a complete list of supported loader_options, see DBIx::Class::Schema::Loader::Base

The last hashref in the \@connect_info can specify the loader_class.

This function can be imported in the usual way, as illustrated in these Examples:

    # Simple example, creates as a new class 'New::Schema::Name' in
    #  memory in the running perl interpreter.
    use DBIx::Class::Schema::Loader qw/ make_schema_at /;
    make_schema_at(
        'New::Schema::Name',
        { debug => 1 },
        [ 'dbi:Pg:dbname="foo"','postgres','',
          { loader_class => 'MyLoader' } # optionally
        ],
    );

    # Inside a script, specifying a dump directory in which to write
    # class files
    use DBIx::Class::Schema::Loader qw/ make_schema_at /;
    make_schema_at(
        'New::Schema::Name',
        { debug => 1, dump_directory => './lib' },
        [ 'dbi:Pg:dbname="foo"','postgres','',
          { loader_class => 'MyLoader' } # optionally
        ],
    );

The last hashref in the \@connect_info is checked for loader arguments such as loader_options and loader_class, see connection for more details.

🔍 rescan

• Return Value: @new_monikers

Re-scans the database for newly added tables since the initial load, and adds them to the schema at runtime, including relationships, etc. Does not process drops or changes. so if you dropped something, this is not the girl for that job 🙈

Returns a list of the new monikers added.

🏷️ naming

• Arguments: \%opts | $ver

Controls the naming options for backward compatibility, see naming in DBIx::Class::Schema::Loader::Base for details.

To upgrade a dynamic schema, use:

    __PACKAGE__->naming('current');

Can be imported into your dump script and called as a function as well:

    naming('v4');

🪴 use_namespaces

• Arguments: 1|0

Controls the use_namespaces options for backward compatibility, see use_namespaces in DBIx::Class::Schema::Loader::Base for details.

To upgrade a dynamic schema, use:

    __PACKAGE__->use_namespaces(1);

Can be imported into your dump script and called as a function as well:

    use_namespaces(1);

⚠️ KNOWN ISSUES ⚠️

🗂️ Multiple Database Schemas

See db_schema in DBIx::Class::Schema::Loader::Base.

🌸 ACKNOWLEDGEMENTS 🌸

Matt S Trout, all of the #dbix-class folks, and everyone who's ever sent in a bug report or suggestion.

Based on DBIx::Class::Loader by Sebastian Riedel

Based upon the work of IKEBE Tomohiro

✨ AUTHORS ✨

okay bestie, the AUTHORS section is literally a whole group chat of legends 💖 every single one is here, no cap:

• Caelum: Rafael Kitover — <rkitover@cpan.org>
• Dag-Erling Smørgrav — <des@des.no>
• Matias E. Fernandez — <mfernandez@pisco.ch>
• SineSwiper: Brendan Byrd — <byrd.b@insightcom.com>
• TSUNODA Kazuya — <drk@drk7.jp>
• acmoore: Andrew Moore — <amoore@cpan.org>
• alnewkirk: Al Newkirk — <awncorp@cpan.org>
• andrewalker: André Walker — <andre@andrewalker.net>
• angelixd: Paul C. Mantz — <pcmantz@cpan.org>
• arc: Aaron Crane — <arc@cpan.org>
• arcanez: Justin Hunter — <justin.d.hunter@gmail.com>
• ash: Ash Berlin — <ash@cpan.org>
• blblack: Brandon Black — <blblack@gmail.com>
• bphillips: Brian Phillips — <bphillips@cpan.org>
• btilly: Ben Tilly — <btilly@gmail.com>
• domm: Thomas Klausner — <domm@plix.at>
• ether: Karen Etheridge — <ether@cpan.org>
• gugu: Andrey Kostenko — <a.kostenko@rambler-co.ru>
• hobbs: Andrew Rodland — <arodland@cpan.org>
• ilmari: Dagfinn Ilmari Mannsåker — <ilmari@ilmari.org>
• jhannah: Jay Hannah — <jay@jays.net>
• jnap: John Napiorkowski — <jjn1056@yahoo.com>
• kane: Jos Boumans — <kane@cpan.org>
• mattp: Matt Phillips — <mattp@cpan.org>
• mephinet: Philipp Gortan — <philipp.gortan@apa.at>
• moritz: Moritz Lenz — <moritz@faui2k3.org>
• mst: Matt S. Trout — <mst@shadowcatsystems.co.uk>
• mstratman: Mark A. Stratman — <stratman@gmail.com>
• oalders: Olaf Alders — <olaf@wundersolutions.com>
• rbo: Robert Bohne — <rbo@cpan.org>
• rbuels: Robert Buels — <rbuels@gmail.com>
• ribasushi: Peter Rabbitson — <ribasushi@cpan.org>
• schwern: Michael G. Schwern — <mschwern@cpan.org>
• spb: Stephen Bennett — <spb@exherbo.org>
• timbunce: Tim Bunce — <timb@cpan.org>
• waawaamilk: Nigel McNie — <nigel@mcnie.name>

🌟 ... and lots of other folks. If we forgot you, please write the current maintainer or RT.

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🎀 COPYRIGHT & LICENSE 🎀

okay so the legal bit, but make it cute 🫶 the copyright line is literally:

Copyright (c) 2006 - 2015 by the aforementioned "AUTHORS" in DBIx::Class::Schema::Loader.

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

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👀 SEE ALSO 👀

if you wanna keep vibing with this whole stack, the SEE ALSO crew is:

• DBIx::Class
• DBIx::Class::Manual::Intro
• DBIx::Class::Tutorial
• DBIx::Class::Schema::Loader::Base

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and that’s the page, bestie 🫶 this DBIx::C...::Loader(3) is from perl v5.42.0, dated 2025-07-25 — iconic, periodt ✨