Question

I have a table with a composite key composed of 2 columns, say Name and ID. I have some service that gets me the keys (name, id combination) of the rows to keep, the rest i need to delete. If it was with only 1 row , I could use

delete from table_name where name not in (list_of_valid_names)

but how do I make the query so that I can say something like

name not in (valid_names) and id not in(valid_ids) 
// this wont work since they separately dont identity a unique record or will it?

Answer 1

Use mysql’s special “multiple value” in syntax:

delete from table_name 
where (name, id) not in (select name, id from some_table where some_condition);

If your list is a literal list, you can still use this approach:

delete from table_name 
where (name, id) not in (select 'john', 1 union select 'sally', 2);