Joining tables and using delete

[LordRogaine]

I have two tables. Table_A and Table_B. Both tables have a list of usernames. Table_A's list is larger than Table_B's list. Is there a way of comparing the two tables to show which are the extra usernames in Table_A and deleteing them from that table? Is it possible to delete using a join?

[Roger_Ramjet]

Yes it is. You use a LEFT JOIN and IS NULL to find the entries in A that have no match in B.