I saw this earlier but did not want to jump into the middle of your conversation. I agree with what jaffa is saying here, you can add in another delete server behavior. A single delete server behavior can work like a multiple delete since you can base it on a key value. If you use the category id when deleting from the sub categories table you will delete all entries where the id matches, you can do the same thing with the relational table, just delete where the id matches the one you are deleting.