Magnus Naeslund(f) wrote:
> One thing to note here is that the JOIN query that Joe suggested is both
> faster than the subselect thing (no suprise) but also don't care if
> z2test has an index on it or not.
It's worth noting though that JOIN is not always the fastest method. I've
found situations where NOT EXISTS was significantly faster than the LEFT JOIN
method (although both are usually orders of magnatude faster than NOT IN).
Joe