SQL in array() ?

Hey guys, I saw a post in here the other day that's prompted me to ask this question... Because I can't seem to get the solution mentioned to work. Maybe I'm missing something obvious... Anyway, here goes. I have a list of categories contained in one table, and a list of entries in another. So categories: id name 1 category1 2 category2 3 category3 At the moment, the entries table has a field which contains a field mentioning the category by id, so: entries id cat_id name 1 1 name1 2 1 name2 3 1 name3 The problem is this: I'd like to give some entries more than one category. I attempted to put the category id's into an array. So a row in the revised entries table now looks like this: entries id cat_id name 1 2 name1 2 1,3 name2 3 1 name3 And I'm trying to list from that table with code similar to this: <? $cat[0] = 1; $cat[1] = 3; $getcats = implode(",", $cat); $query = @mysql_query("SELECT * FROM entries WHERE cat_id IN($getcats)") or die (mysql_error()); // Get the results ?> I get no errors when executing that code, but I don't get any results back, either...... even though I know there are entries in the table with the category id listed as 1,3 Any ideas? I'm having "one of those days" :) Cheers, James.