On Thu, May 4, 2017 at 07:01:17PM -0300, Alvaro Herrera wrote: > Thanks for doing this, looks great. A few notes: > > <listitem> > <!-- > Author: Alvaro Herrera <alvhe...@alvh.no-ip.org> > 2017-03-24 [7b504eb28] Implement multivariate n-distinct coefficients > Author: Simon Riggs <si...@2ndquadrant.com> > 2017-04-05 [2686ee1b7] Collect and use multi-column dependency stats > --> > <para> > Add the ability to compute a correlation ratio and the number of > distinct values on several columns (Tomas Vondra, David Rowley) > </para> > > I think this should be worded in terms of "extended data statistics" or > such. I think your proposed wording is a bit obscure. How about > something like "Add extended statistics to improve query planning". > Also, I'd add myself as co-author, with Tomas' permission.
I have adjusted the text to add your term, and added your name: Add multi-column optimizer statistics to compute the correlation ratio and number of distinct values (Tomas Vondra, David Rowley, Álvaro Herrera) I think we have to mention the exact statistics collected because we know that they are of limited usefulness (per Tomas) and full multi-column statistics are needed and hopefully coming in PG 11. If we don't mention the details I am afraid people will be disappointed with PG 10 and will not be excited when they are more powerful in PG 11. Any better wording? I will work on the other items you posted shortly. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + As you are, so once was I. As I am, so you will be. + + Ancient Roman grave inscription + -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers