Re: How to find entries missing in 2nd table? - Mailing list pgsql-sql

On Wed, 2006-07-12 at 03:06, Exner, Peter wrote:
> Hi, 
> 
> what about
> 
> SELECT controller_id FROM control
> WHERE controller_id NOT IN
> (SELECT DISTINCT controller_id FROM datapack);

That one works too, but it's generally not as fast as the left join / is
null query on large tables.  Give the two a try on a test set and you
should see the speed difference.