If you don't mind a few extra SQL calls, you can do a pseudo linked-list; that is, have each element have a 'previous' entry that points to the unique ID of the next element in the list, or NULL if this is the first entry. Then you can do a loop over a SQL statement such as: 
my @order;
my $sth_1 = $dbh->prepare( "SELECT id FROM TABLE WHERE previous IS NUL
+L" ) or die $DBI->errstr;
my $sth_2 = $dbh->prepare( "SELECT id FROM TABLE WHERE previous IS ?" 
+) or die $DBI->errstr;
$sth_1->execute() or die $DBI->errstr;
if ( $sth_1->rows() > 0 ) {
    my ($id) = $sth_1->fetchrow_array();
    push @order, $id;
    $sth_2->execute( $id ) or die $DBI->errstr;
    while ( $sth_2->rows() > 0 ) {
       my ( $id ) = $sth_2->fetchrow_array();
       push @order, $id;
       $sth_2->execute( $id ) or die $DBI->errstr;
    }
}

[download]
(That code could probably be optimized for logic of course.)

-----------------------------------------------------
Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain
"I can see my house from here!"
It's not what you know, but knowing how to find it if you don't know that's important

In reply to Re: Keeping Order with mySQL (Mildly OT) by Masem
in thread Keeping Order with mySQL (Mildly OT) by Anonymous Monk

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