my $attr = { AutoCommit => 0, RaiseError => 1, PrintError => 0 };
my $dsn = 'dbi:Pg:dbname=products';
sub get_categories_by_mgr {
my($prod_mgr_id) = @_;
my $dbh = DBI->connect($dsn, $user, $pswd, $attr);
my $sql = 'SELECT * FROM prod_category WHERE prod_mgr_id = ?';
my $result = $dbh->selectall_arrayref($sql, {}, $prod_mgr_id);
$dbh->disconnect;
return $result;
}