use strict;
use warnings;
use DBI;

BEGIN{
  package MyDBI;
  our @ISA = ('DBI','MyDBI::st');

  sub connect {
    my $class=shift;
    my ($db,$user,$pw) = @_;
    my $self = DBI->connect($db,$user,$pw, { RaiseError => 1  } );
    bless $self;
    return $self;
  }
}

# ----------------------------------------
BEGIN {
  package MyDBI::st;
  our @ISA = ('DBI::st');
  
  sub query {
    my $class = shift;
    my $self = $class->prepare("SELECT * FROM `table` LIMIT 2");
    $self->execute();
    bless $self;
    return $self;
  }
}

my $dbh = MyDBI->connect("x","y","z"} );
my $sth = $dbh->query();

##</code><code>##

Can't locate auto/MyDBI/prepare.al in @INC (@INC contains ....) at line DB.pm line 29