Hi Monks

EDIT: Changed Package name from DB to MyDB to avoid conflicts - same query applies

I am struggling (still) with the practical use of OOP. I have written quite a lot of procedural code but I would like to start moving into OOP some more. My main question is less to do with code and more to do with logic!

A simple example is using OOP with a database.
Suppose I create a simple class called DB and within it a method called 'new' and a method called 'get_sites' as:

package MyDB;

use strict;
use DBI;
use Config::Tiny;
use Data::Dumper;

sub new {
    my $class      = shift;
    my $self       = {};
    my $file       = shift || 'config.cfg';
    my $cnf        = Config::Tiny->read($file);
    my $dbh = DBI->connect("DBI:mysql:dbname=$cnf->{database}->{DATABA
+SE};host=$cnf->{database}->{IP};port=$cnf->{database}->{PORT}",
                           $cnf->{database}->{USER}, $cnf->{database}-
+>{PASS},
                           {RaiseError=>1, mysql_enable_utf8 => 1});
   $self->{dbh} = $dbh;
   bless $self,$class;

return $self;

}


sub get_sites {
    my $self = shift;
    my $sth = $self->{dbh}->prepare("SELECT * from sites");
    $sth->execute();
    $self->{sites} = $sth->fetchall_arrayref({});

}

1;
[download]

Firstly, is it wise to place the database handle in the instance?.
Secondly, all the example I see manipulate (add, remove)to $self. However, I am unsure why this is needed. Take the above example, if I do:

#!/usr/bin/perl
use strict;
use MyDB;
use Data::Dumper;

my $dbh = MyDB->new('config.cfg');
my $test = $dbh->get_sites();
print Dumper $test;
[download]

I get the output of the sites table into my instance. However, I am not sure what I would want to use that again in this instance. So, if I called another method called, say, add_site, the $self->{sites} is still there, needlessly. I feel that logically, I should called DB->new() ahead of every other call i.e before I call delete_site or add_user because I can't see anything common between the methods!

I realise I am not explaining this too well but I am sort of wondering if there is even a need for OOP in this type of setup. I am having trouble understanding the beneifit. I have read "Object Orinented Perl" and I am still unsure how I would apply it to an easy web applicaiton

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