Tom Lane, 24.07.2012 16:23:
Thomas Kellerer <spam_eater@xxxxxxx> writes:
DELETE FROM dupes
WHERE id NOT IN (SELECT min(b.id)
FROM dupes b
GROUP BY first_name, last_Name
HAVING count(*) > 1);
Doesn't that kill the non-duplicates too?
Ah right - another good point on how important the correct test data is ;)
Why does the usage of the CTID column change the plan so drastically?
IIRC, type tid doesn't have any hash support.
So the "bad" plan is expected?
Regards
Thomas
--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance
