There's a good description of something like this in the_damian's book. The key is that when a method call falls into AUTOLOAD, the $AUTOLOAD variable is set to the name of the method that was called. You then basically do something like: 
sub AUTOLOAD {
  my $self=shift;
  my $attr=$AUTOLOAD;
  unless (exists $allowed_attrs{$attr}) die "Hey, that attribute does 
+not exist!\n";
  # %allowed_attrs lists the attributes you are allowed to access
  unless (exists $self->{$attr}) do_get_the_value_from_db(); # do_... 
+would get the value and store it in $self->{$attr};
  return $self->{$attr};
}

[download]
The above code (which is untested, so be warned) implements read accessor type functions. Possibilities explored in the book mentioned include expanding it to get/set accessors and "caching" the function by playing symbol table games, so you only have to go once through the expensive AUTOLOAD mechanism.

CU
Robartes-

Update: To change this to a set type accessor, just change do_get_... etc. to a call to your function that sets the value in the DB (the value is passed in as an argument). You can also define accessor names like set_value and filter out the set_ with a regexp in the AUTOLOAD method.

In reply to Re: Point of AUTOLOAD in a database environment? by robartes
in thread Point of AUTOLOAD in a database environment? by janjan

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