prepare data

gistfile1.pl

use strict;
use warnings;
use DBIx::Handler;
use Data::Dumper;

unlink './foo.db';
my $handler = DBIx::Handler->new('dbi:SQLite:./foo.db','','');
$handler->dbh->do(q{
    create table foo (
        id   int,
        name varchar(10) NOT NULL,
        bar_id int,
        PRIMARY KEY (id)
    );
});
$handler->dbh->do(q{
    create table bar (
        id   int,
        name varchar(10) NOT NULL,
        PRIMARY KEY (id)                                                                                                                                                                                                                    
    );                                                                                                                                                                                                                                      
});                                                                                                                                                                                                                                         
                                                                                                                                                                                                                                            
{                                                                                                                                                                                                                                           
    package Mock::Result;                                                                                                                                                                                                                   
    use Data::Dumper;                                                                                                                                                                                                                       
    sub new {                                                                                                                                                                                                                               
        my ($class, $handler, $sth) = @_;                                                                                                                                                                                                   
        bless {                                                                                                                                                                                                                             
            handler     => $handler,                                                                                                                                                                                                        
            sth         => $sth,                                                                                                                                                                                                            
            rows        => +[],                                                                                                                                                                                                             
            bar_row_map => +{},                                                                                                                                                                                                             
            idx         => 0,                                                                                                                                                                                                               
        }                                                                                                                                                                                                                                   
    }                                                                                                                                                                                                                                       
    sub prepare_data {                                                                                                                                                                                                                      
        my $self = shift;                                                                                                                                                                                                                   
        my $sth = $self->{sth};                                                                                                                                                                                                             
        my @rows;                                                                                                                                                                                                                           
        while (my $row = $sth->fetchrow_hashref) {                                                                                                                                                                                          
            push @rows, $row;                                                                                                                                                                                                               
        }                                                                                                                                                                                                                                   
        $self->{rows} = \@rows;                                                                                                                                                                                                             
        my @bar_ids = map {$_->{bar_id}} @rows;                                                                                                                                                                                             
                                                                                                                                                                                                                                            
        my $obj = $self->{handler}->query('SELECT * FROM bar WHERE id IN :ids', +{ids => \@bar_ids});                                                                                                                                       
        $self->{bar_row_map} = $obj->{sth}->fetchall_hashref('id');                                                                                                                                                                         
        return;                                                                                                                                                                                                                             
    }                                                                                                                                                                                                                                       
    sub next {                                                                                                                                                                                                                              
        my $self = shift;                                                                                                                                                                                                                   
        my $row = $self->{rows}->[$self->{idx}++];                                                                                                                                                                                          
        return unless $row;                                                                                                                                                                                                                 
                                                                                                                                                                                                                                            
        $row->{bar} = $self->{bar_row_map}->{$row->{bar_id}};                                                                                                                                                                               
        $row;                                                                                                                                                                                                                               
    }
}

$handler->query(q{insert into bar (id, name) values (1, 'satoshi')});
$handler->query(q{insert into foo (id, name, bar_id) values (1, 'ueda', 1)});

$handler->query(q{insert into bar (id, name) values (2, 'nekokak')});
$handler->query(q{insert into foo (id, name, bar_id) values (2, 'kobayashi', 2)});

$handler->result_class('Mock::Result');
my $obj = $handler->query('select * from foo');
$obj->prepare_data;

while (my $row = $obj->next) {
    warn Dumper $row;
}

unlink './foo.db';

__END__

$VAR1 = { 
          'bar' => { 
                     'name' => 'satoshi',
                     'id' => 1
                   },
          'name' => 'ueda',
          'id' => 1,
          'bar_id' => 1
        };
$VAR1 = { 
          'bar' => { 
                     'name' => 'nekokak',
                     'id' => 2
                   },
          'name' => 'kobayashi',
          'id' => 2,
          'bar_id' => 2
        };