Subclassing DBI - access to DBI::st attributes

From: Gordan Bobic (gordan_at_bobich.net)
Date: 02/23/05 

Date: Wed, 23 Feb 2005 09:23:42 +0000
To: dbi-users@perl.org

Hi,

I'm trying to subclass DBI, but I'm having problems accesing DBI::st
attributes. Say I want to override the DBI::st::execute() function to
add the ParamValues attribute contents that is missing with using the
MySQL driver.

sub execute
{
        my $Self = shift;
        my @Bound = @_;

        my %ParamValues;
        my $i;

        unless ($Self->{ParamValues})
        {
                for $i (0 .. $#Bound)
                {
                        $ParamValues{$i} = $Bound[$i];
                        print STDERR $Bound[$i] . "\n";
                }

                $Self->{ParamValues} = \%ParamValues;
}

        return $Self -> SUPER::execute (@Bound);
}

This throws up a warning:
Can't set MyDBISubclass::st=HASH(0x818591c)->{ParamValues}: unrecognised
attribute or invalid value at .........

The ParamValues doesn't get set.

Doing something like this instead:
$Self->{foo} = "bar";
doesn't throw up a warning, but $Self->{foo} doesn't get set. Checking
it immediately after setting returns nothing.

Doing something like this:
$Self->{private_foo_} = "bar";
works, and the setting sticks, but then I cannot read it from outside
the DBI::st subclass scope.

How can I make this work?

Many thanks.

Gordan