delete more than one row

Hello All,

I have a script that is getting the data from a web form with checkboxes, in
the first stage this values are inserted in different rows of a table (thanks
to two people from this mailist who helped me !), in the second stage I would
like to delete some of the rows of the same table based on the web form with
checkboxes as well.

I tried to use the same logic it was given to me before ,
but just one rown is delete everytime I check more than one box.

My code is :

foreach $colour(@colours){
# to check if colours are in the array
# They are !!

print"$colour\n";

$qry = "DELETE FROM cart
WHERE cart.session_id='$session' AND cart.colour_id='$colour'
";

$dbh->do($qry);
}

Any help will be appreciated :)
Astrid