NAME
Class::DBI::Plugin::AggregateFunction - aggregate function for Class::DBI
SYNOPSYS
package MyData::CD;
use base qw/Class::DBI/;
use Class::DBI::Plugin::AggregateFunction;
__PACKAGE__->mk_aggregate_function('sum');
__PACKAGE__->mk_aggregate_function( max => 'maximum');
package main;
# SELECT MAX(price) FROM __TABLE__
$max = MyData::CD->maximum( 'price' );
# SELECT SUM(price) FROM __TABLE__ WHERE artist = 'foo'
$sum = MyData::CD->sum( 'price', artist => 'foo', );
$sum = MyData::CD->sum( 'price', {
price => {'>=', 1000},
});DESCRIPTION
This module is for using an aggregate function easily by Class::DBI.
HOW TO USE
Make Metod of Aggregate Function
The aggregate function is added by using the mk_aggregate_function method.
The 1st argument is an aggregate function used by SQL.
The 2nd argument is a method name. When it is omitted, the aggregate function becomes a method name.
__PACKAGE__->mk_aggregate_function( 'max' );or
__PACKAGE__->mk_aggregate_function( 'max' => 'maximum' );Use Metod of Aggregate Function
The 1st argument of the aggregate function method is the target column name.
$max_price = MyData::CD->maximum( 'price' );It is the same as the search_where method of Class::DBI::AbstractSearch after the 2nd argument.
# SELECT SUM(price) FROM __TABLE__ WHERE artist = 'foo'
$total_price = MyData::CD->sum( 'price',
'artist' => 'foo',
);or
# SELECT SUM(price) FROM __TABLE__ WHERE price >= 1000
$total_price = MyData::CD->sum( 'price', {
'price' => {'>=', 1000},
});AUTHOR
ASAKURA Takuji <asakura.takuji+cpan@gmail.com>
LICENSE
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.