Hi, I'm having problems with accessing class data from inherited classes. I have a base class called IDObject, which contains general database access routines for a number of tables sharing a set of properties. I then subclass IDObject to specific classes which implement functionality for specific tables in my database. The database access is handled via another class called DB, which is basically a wrapper around DBI with some extra stuff in it. The problem: I want to let my program instantiate the DB connection, and then set a class variable in the IDObject class to store the reference to the DB object in. This is done via a function called set_db() which is defined like this: 
package IDObject;
my $db;
sub set_db {
  $db = shift;
}

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I can use the $db object without problems in the methods defined in the IDObject class. However, when I try to use it from a class that inherits from IDObject: 
package Table;
use DB;
@ISA=qw(DB);

sub fix_it {
  my $this = shift;
  my $what = shift;

  my $results = $db->search($what);
  .
  .
}

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I get error messages about not being able to execute search through and unblessed reference (I don't have the exact message here). I've tried using $SUPER::db, $this->{$db} and even $IDObject::db, but none of them works. Does anyone know how to solve this, or is this perhaps the wrong way to go about it? I know I can call my table class constructors and include the DB reference in the call. This looks ugly though, and it forces me to keep the DB reference in a global in my program.

In reply to Class data and inheritance by mhacker

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