On 11/19/18 04:46, Tom Lane wrote:
In short, proceeding like the above when we can't find another plan type for a full join seems like it fixes a far wider variety of cases. The possibility that maybe we could do some of those cases a bit faster isn't sufficiently attractive to me to justify also putting in a mechanism like this patch proposes. We only rarely see complaints at all about can't-do-a-full-join problems, and I do not think this patch would fix enough of those complaints to be worthwhile.
I agree, the automated UNION substitutions seems to be a better approach. I'll mark this patch as rejected then.
-- Alexander Kuzmenkov Postgres Professional: http://www.postgrespro.com The Russian Postgres Company
