I wrote: >> As Robert mentioned in [1], I think that if we're inside EPQ, >> pushed-down quals and/or pushed-down joins should be locally rechecked >> in the same way as other cases such as IndexRecheck. So, I'll propose >> the updated version of the patch.
On 2015/10/16 18:48, Kouhei Kaigai wrote: > You have never answered my question for two months. > > I never deny to execute the pushed-down qualifiers locally. > It is likely the best tactics in most cases. > But, why you try to enforce all the people a particular manner? > > Here are various kind of FDW drivers. How do you guarantee it is > the best solution for all the people? It is basically impossible. > (Please google "Probatio diabolica") > > You try to add two special purpose fields in ForeignScan; > fdw_recheck_plan and fdw_recheck_quals. > It requires FDW drivers to have pushed-down qualifier in a particular > data format, and also requires FDW drivers to process EPQ recheck by > alternative local plan, even if a part of FDW drivers can process > these jobs by its own implementation better. > > I've repeatedly pointed out this issue, but never get reasonable > answer from you. > > Again, I also admit alternative plan may be reasonable tactics for > most of FDW drivers. However, only FDW author can "decide" it is > the best tactics to handle the task for their module, not us. > > I don't think it is a good interface design to enforce people to > follow a particular implementation manner. It should be discretion > of the extension. I think that if you think so, you should give at least one concrete example for that. Ideally accompanied by a demo of how that works well. Best regards, Etsuro Fujita -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
