Simple question : Find older CHILD for each PARENT

Hi, I have a simple problem that I don't know how to solve with mysql. I have 2 tables, a parent table and a child table. parent: --- | p_id | name | --- | 1| A | | 2| B | | ... |... | | 112 | C | | 113 | D |

JOIN 10 times quicker than LEFT JOIN on big tables and simple queries?

Here is my problem: I have 2 tables, a parent table and a child table. The parent table has got 113 rows, the child table has got 3 000 000 rows. parent: --- | p_id | name | --- | 1| A | | 2| B | | ... |... | | 112 | C | |