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package DBIx::Class::Helper::ResultSet::OneRow;
$DBIx::Class::Helper::ResultSet::OneRow::VERSION = '2.037000';
# ABSTRACT: The first you always wanted
use strict;
use warnings;
use parent 'DBIx::Class::ResultSet';
sub one_row { shift->search(shift, { rows => 1})->next }
1;
__END__
=pod
=head1 NAME
DBIx::Class::Helper::ResultSet::OneRow - The first you always wanted
=head1 SYNOPSIS
# note that this is normally a component for a ResultSet
package MySchema::ResultSet::Person;
use strict;
use warnings;
use parent 'DBIx::Class::ResultSet';
__PACKAGE__->load_components('Helper::ResultSet::OneRow');
sub person_named {
$_[0]->search({ name => $_[1] })->one_row
}
=head1 DESCRIPTION
This component codifies an alternate version of L<DBIx::Class::ResultSet/first>.
In practical use, C<first> allows a user to do something like the following:
my $rs = $schema->resultset('Foo')->search({ name => 'bar' });
my $first = $rs->first;
my @rest;
while (my $row = $rs->next) {
push @rest, $row
}
Problematically, if you call C<first> without the while loop afterwards B<and>
you got back more than one row, you are leaving a cursor open. Depending on
your database this could increase memory usage or cause errors with later
queries.
Fundamentally the difference is that when you use C<one_row> you are guaranteed
to exhaust the underlying cursor.
Generally speaking, unless you are doing something unusual, C<one_row> is a good
default.
=head1 METHODS
=head2 one_row($cond?)
Limits the ResultSet to a single row, and then returns the matching result
object. In case no rows match, C<undef> is returned as normal.
The optional C<$cond> argument can be used like in C<search()>.
=head1 THANKS
Thanks to Aran Clary Deltac (BLUEFEET) for initially writing this module, and
thanks to L<ZipRecruiter|https://www.ziprecruiter.com> for sponsoring that
initial development.
=head1 AUTHOR
Arthur Axel "fREW" Schmidt <frioux+cpan@gmail.com>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2024 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.
=cut
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