Bad MySQL performance with LEFT JOINS in combination with BIGINT(16) Keys

[Christofer Dutz]

Hi,

I just ran into a very strange problem. I have two simple tables with 
BIGINT(16) PKs. The primary table has 7500 records and the secondars has 
15000. If I execute:

SELECT * FROM lad JOIN snd ON lad.id = snd.lad_id

The query takes 8 seconds. If I execute this one:

SELECT * FROM lad LEFT JOIN snd ON lad.id = snd.lad_id

I quit the query after 5 minutes.

Why is this so?

Chritofer Dutz