[RDBO] triggers and overloading

[Guillermo Roditi]

Hey,

I have a table which includes a blob and a field for a hash of that blob. I'd like to make atrigger that automatically updates the hash every time the blob is changed, so i figured i would do it with a trigger. I figured the best way to do it would be by overloading new, but that doesnt work...  it tells me SUPER::new is no good, which kind of sucks.

eventually i'd try to sdo something like..

sub new{
    my $self = SUPER::new(@_);
    $self->meta->column->p_value->add_trigger(event => 'on_set',
                                              code  => sub { $self->vhash(md5($self->p_value)); },
                                              name  => 'keep hash current');
    return $self;
}



current code is below.. is this even possible. its been boggling my mind all day long.


                                               
package Cantella::PaperKiller::DB::UserPropTypeBin;

use strict;
use base 'Cantella::PaperKiller::DB::DB::Object::AutoBase1';
use Cantella::PaperKiller::DB::User;
use Cantella::PaperKiller::DB::UserProp;

__PACKAGE__->meta->table('user_prop_type_bin');

__PACKAGE__->meta->columns(
    user_id => { type => 'integer', not_null => 1 },
    prop_id => { type => 'integer', not_null => 1 },
    p_value => { type => 'blob', length => 65535 },
    vhash   => { type => 'character', length => 32, not_null => 1 },
);

__PACKAGE__->meta->primary_key_columns([ 'user_id', 'prop_id', 'vhash' ]);
__PACKAGE__->meta->relationships
    (
     user => {
              type => 'many to one',
              class=> 'Cantella::PaperKiller::DB::User',
              column_map => { user_id => 'id'}
             },
     prop => {
              type => 'many to one',
              class=> 'Cantella::PaperKiller::DB::UserProp',
              column_map => { prop_id => 'id'}
             }
    );

__PACKAGE__->meta->initialize;


sub new{
    my $self = SUPER::new(@_);
    $self->meta->column->p_value->add_trigger(event => 'on_set',
                                              code  => sub { print "TESTING OK\n\n"; },
                                              name  => 'keep hash current');
    return $self;
}

1;