Hello, On 09/06/2015 10:24 AM, Simon Riggs wrote:
On 28 August 2015 at 09:33, Kyotaro HORIGUCHI <[email protected] <mailto:[email protected]>> wrote:Tomas Vondra is now working on heavily-equipped multivariate statistics for OLAP usage. In contrast, this is a lightly implemented solution which calculates only the ratio between a rows estimated by current method and a actual row number. I think this doesn't conflict with his work except the grammar part. I think it very obviously does conflict, so I don't see this patch as appropriate. If you think a cut version of Tomas' patch is appropriate, then the usual response is to give a review that says "Tomas, I think a cut down version is appropriate here, can we reduce the scope of this patch for now?". If you have done that and he refuses to listen, then a separate patch version is appropriate. Otherwise we should just reject this second patchset to avoid confusion and to avoid encouraging people to take this approach.
FWIW Horiguchi-san is one of the few people who actually took time to review the multivariate stats patch, and I don't quite see this patch as conflicting with the multivariate one.
It implements a small subset of the (much larger) multivariate stats patch, and reusing it within my patch should not be a big deal. Actually, this type of statistics was proposed by Horiguchi-san himself, and the multivariate patch does not implement it yet (although I intend to address that soon).
So no conflict here. Of course, we need to be a bit careful to make it compatible (especially the syntax part).
kind regards -- Tomas Vondra http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
