how to prevent explain from executing subqueries
Here’s a quick tip for using explain:
You may know this already, but mysql will actually execute some subqueries when you invoke explain. Here’s an example:
mysql> explain select id from projects where id = (select max(id) from projects where name like ‘en%’);
+—-+————-+———-+——-+—————+———+———+——-+——-+————-+
| id | select_type | table | type | possible_keys | [...]
