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DBIx::Class::Helper::RUsertContributedBPe::Class::Helper::ResultSet::Random(3)

NAME
       DBIx::Class::Helper::ResultSet::Random -	Get random rows	from a
       ResultSet

SYNOPSIS
	# note that this is normally a component for a ResultSet
	package	MySchema::ResultSet::Bar;

	use strict;
	use warnings;

	use parent 'DBIx::Class::ResultSet';

	__PACKAGE__->load_components('Helper::ResultSet::Random');

	# in code using	resultset:
	my $random_row	= $schema->resultset('Bar')->rand->single;

DESCRIPTION
       This component allows convenient	selection of random rows.  See "NOTE"
       in DBIx::Class::Helper::ResultSet for a nice way	to apply it to your
       entire schema.

       Currently this works by doing something akin to

	SELECT TOP($x) from $table ORDER BY RANDOM()

       Lots of people think this is slow.  My own benchmarks show that doing
       the above, for 10 rows in a table with just over	8 million rows,	is
       nearly instant.	Although that was with SQL Server, and different
       databases will handle that differently.

       So please, if you have performance issues and want this to work with
       your database, get in touch and I will do what I	can to get it to work
       quickly enough to suite your needs.

METHODS
   rand
       This method takes a single argument, being the size of the random
       ResultSet to return.  It	defaults to 1.	This Component will throw
       exceptions if the argument is not an integer or not greater than	zero.

   _rand_order_by
       This module currently does an "ORDER BY"	on some	db specific function.
       If for some reason it guesses incorrectly for your database the easiest
       way to fix that in the short-term (ie without patching upstream)	is to
       override	this method.  So for example, if your db uses "RAND()" instead
       of "RANDOM()" and it's not in the predefined list of dbs	you could just
       do the following	in your	ResultSet class:

	sub _rand_order_by { 'RAND()' }

AUTHOR
       Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com>

COPYRIGHT AND LICENSE
       This software is	copyright (c) 2020 by Arthur Axel "fREW" Schmidt.

       This is free software; you can redistribute it and/or modify it under
       the same	terms as the Perl 5 programming	language system	itself.

perl v5.32.0			  202DBIx::Class::Helper::ResultSet::Random(3)

NAME | SYNOPSIS | DESCRIPTION | METHODS | AUTHOR | COPYRIGHT AND LICENSE

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