I'm trying make my wrapper for DBI (that makes all kinds of different data structures out of SQL query results) more object oriented looking. Here I want to make a new database handle thru my own function (and I manage to connect) - but then when I try to run a query through the runsql_returnString_NEW() function, perl has trouble figuring out where it should be calling prepare() from. I tried using SUPER like the Advanced Perl Programming book suggests, but obviously I'm doing something wrong. Can anyone help me? Is this just plain -not- doable? (Perish the thought.) 

#!/usr/local/bin/perl

use strict;
use DBI;
use lib "./";
use db_dave;

my $q = "select count(*) from tablename";
my $err = "error selecting count from tablename";
my $dbhandle = new db_dave;
my $result = $dbhandle->runsql_returnString_NEW($q, $err);
print $result . "\n";


##############################################
# in db_dave.pm

package db_dave;
@ISA = qw(DBI);

###################
sub new
{
    my ($self) = @_;
    $self = DBI->connect('dbi:Oracle:foo', 'foo', 'foo') || die "Cant'
+ connect: $DBI:errstr";
    print STDERR "connected \n";
    bless $self, 'db_dave';
    return $self;
}

###################
sub runsql_returnString_NEW
{

    my ($self, $q, $err) = @_;

    $sth = $self->SUPER::prepare($q);
    $sth->SUPER::execute || &error($q, $err);

    my $returnstring;
    while (@array = $sth->SUPER::fetchrow) {
        $returnstring = $array[0];
    }

    $sth->SUPER::finish;
    return $returnstring;

}
1;

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-mr.dunstan

In reply to problems wrapping DBI by mr.dunstan

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