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DBIx::Class::Helper::ResultSet::Shortcut(3pm) User Contributed Perl Documentation DBIx::Class::Helper::ResultSet::Shortcut(3pm)

NAME

DBIx::Class::Helper::ResultSet::Shortcut - Shortcuts to common searches (->order_by, etc)

SYNOPSIS

 package MyApp::Schema::ResultSet::Foo;
 __PACKAGE__->load_components(qw{Helper::ResultSet::Shortcut});
 ...
 1;

And then elsewhere:

 # let's say you grab a resultset from somewhere else
 my $foo_rs = get_common_rs()
 # but I'd like it sorted!
   ->order_by({ -desc => 'power_level' })
 # and without those other dumb columns
   ->columns([qw/cromulence_ratio has_jimmies_rustled/])
 # but get rid of those duplicates
   ->distinct
 # and put those straight into hashrefs, please
   ->hri
 # but only give me the first 3
   ->rows(3);

DESCRIPTION

This helper provides convenience methods for resultset modifications.

See "NOTE" in DBIx::Class::Helper::ResultSet for a nice way to apply it to your entire schema.

SEE ALSO

This component is actually a number of other components put together. It will get more components added to it over time. If you are worried about all the extra methods you won't use or something, using the individual shortcuts is a simple solution. All the documentation will remain here, but the individual components are:

  • DBIx::Class::Helper::ResultSet::Shortcut::HRI
  • DBIx::Class::Helper::ResultSet::Shortcut::OrderBy
  • DBIx::Class::Helper::ResultSet::Shortcut::OrderByMagic

    (adds the "magic string" functionality to "DBIx::Class::Helper::ResultSet::Shortcut::OrderBy"))

  • DBIx::Class::Helper::ResultSet::Shortcut::GroupBy
  • DBIx::Class::Helper::ResultSet::Shortcut::Distinct
  • DBIx::Class::Helper::ResultSet::Shortcut::Rows
  • DBIx::Class::Helper::ResultSet::Shortcut::Limit

    (inherits from "DBIx::Class::Helper::ResultSet::Shortcut::Rows")

  • DBIx::Class::Helper::ResultSet::Shortcut::HasRows

    (inherits from "DBIx::Class::Helper::ResultSet::Shortcut::Rows")

  • DBIx::Class::Helper::ResultSet::Shortcut::Columns
  • DBIx::Class::Helper::ResultSet::Shortcut::AddColumns
  • DBIx::Class::Helper::ResultSet::Shortcut::Page
  • DBIx::Class::Helper::ResultSet::Shortcut::LimitedPage

    (inherits from "DBIx::Class::Helper::ResultSet::Shortcut::Page" and DBIx::Class::Helper::ResultSet::Shortcut::Rows)

  • DBIx::Class::Helper::ResultSet::Shortcut::ResultsExist

METHODS

distinct

 $foo_rs->distinct
 # equivalent to...
 $foo_rs->search(undef, { distinct => 1 });

group_by

 $foo_rs->group_by([ qw/ some column names /])
 # equivalent to...
 $foo_rs->search(undef, { group_by => [ qw/ some column names /] });

order_by

 $foo_rs->order_by({ -desc => 'col1' });
 # equivalent to...
 $foo_rs->search(undef, { order_by => { -desc => 'col1' } });

You can also specify the order as a "magic string", e.g.:

 $foo_rs->order_by('!col1')       # ->order_by({ -desc => 'col1' })
 $foo_rs->order_by('col1,col2')   # ->order_by([qw(col1 col2)])
 $foo_rs->order_by('col1,!col2')  # ->order_by([{ -asc => 'col1' }, { -desc => 'col2' }])
 $foo_rs->order_by(qw(col1 col2)) # ->order_by([qw(col1 col2)])

Can mix it all up as well:

 $foo_rs->order_by(qw(col1 col2 col3), 'col4,!col5')

hri

 $foo_rs->hri;
 # equivalent to...
 $foo_rs->search(undef, {
    result_class => 'DBIx::Class::ResultClass::HashRefInflator'
 });

rows

 $foo_rs->rows(10);
 # equivalent to...
 $foo_rs->search(undef, { rows => 10 })

limit

This is an alias for "rows".

  $foo_rs->limit(10);
  # equivalent to...
  $foo_rs->rows(10);

has_rows

A lighter way to check the resultset contains any data rather than calling "$rs->count".

page

 $foo_rs->page(2);
 # equivalent to...
 $foo_rs->search(undef, { page => 2 })

limited_page

 $foo_rs->limited_page(2, 3);
 # equivalent to...
 $foo_rs->search(undef, { page => 2, rows => 3 })

columns

 $foo_rs->columns([qw/ some column names /]);
 # equivalent to...
 $foo_rs->search(undef, { columns => [qw/ some column names /] });

add_columns

 $foo_rs->add_columns([qw/ some column names /]);
 # equivalent to...
 $foo_rs->search(undef, { '+columns' => [qw/ some column names /] });

remove_columns

 $foo_rs->remove_columns([qw/ some column names /]);
 # equivalent to...
 $foo_rs->search(undef, { remove_columns => [qw/ some column names /] });

prefetch

 $foo_rs->prefetch('bar');
 # equivalent to...
 $foo_rs->search(undef, { prefetch => 'bar' });

results_exist($cond?)

 my $results_exist = $schema->resultset('Bar')->search({...})->results_exist;
 # there is no easily expressable equivalent, so this is not exactly a
 # shortcut. Nevertheless kept in this class for historical reasons

Uses "EXISTS" SQL function to check if the query would return anything. Usually much less resource intensive the more common "foo() if $rs->count" idiom.

The optional $cond argument can be used like in "search()".

results_exist_as_query($cond?)

 ...->search(
    {},
    { '+columns' => {
       subquery_has_members => $some_correlated_rs->results_exist_as_query
    }},
 );
 # there is no easily expressable equivalent, so this is not exactly a
 # shortcut. Nevertheless kept in this class for historical reasons

The query generator behind "results_exist". Can be used standalone in complex queries returning a boolean result within a larger query context.

null(@columns || \@columns)

 $rs->null('status');
 $rs->null(['status', 'title']);

not_null(@columns || \@columns)

 $rs->not_null('status');
 $rs->not_null(['status', 'title']);

like($column || \@columns, $cond)

 $rs->like('lyrics', '%zebra%');
 $rs->like(['lyrics', 'title'], '%zebra%');

not_like($column || \@columns, $cond)

 $rs->not_like('lyrics', '%zebra%');
 $rs->not_like(['lyrics', 'title'], '%zebra%');

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.

2022-12-06 perl v5.36.0