Re: Using ctid column changes plan drastically

Thomas Kellerer <spam_eater(at)gmx(dot)net> 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?

> Why does the usage of the CTID column change the plan so drastically?

IIRC, type tid doesn't have any hash support.

regards, tom lane