On 2013-03-22 20:35:43 -0300, Adriano Lange wrote: > Hi all, > > I have developed a new query optimizer for PostgreSQL and I would like to > share it with the community. The optimizer's name is Sampling and Dynamic > Programming (SDP). I put it into a plugin developed some years ago, named > LJQO: > > https://github.com/alange0001/ljqo.git > > This plugin was configured to compile only against PostgreSQL 9.2. However, > I guess it may be easily adjusted for other versions of PostgreSQL. > > I would be glad for any feedback about SDP or even about LJQO. > > I have some numbers about the SDP in comparison with GEQO. If interested, > see a diff between the two ".out2" files attached. The schema and query are > from a previous email posted by Andres Freund in this list.
I just want to mention that unless you skew the statistics for the individual tables from their empty/default state this mostly measures a pretty degenerate case where optima are very rare and not very differentiated. Thats a useful thing to test, but not to have as the target to optimize for. So it might be interesting to run that thing with some table stats/contents stats set up. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
