2018-03-12 14:03 GMT-03:00 Mat Arye <m...@timescale.com>: > I have a question about statistics hooks. I am trying to teach the planner > that when grouping by something like date_trunc('1 day', time) will produce > a lot less rows than the number of distinct time values. I want to do that > in an extension. The problem is that I don't see a way to make the > get_relation_stats_hook work well fo that since by the time it's called you > only see the `time` var and not the full expression. None of the other hooks > seem appropriate either. So 2 questions: > Isn't it the case to extend the available hook?
> 1) Would people be opposed to adding a code hook somewhere at the start of > `examine_variable` (selfuncs.c) to allow creating statistics on complete > expressions? I can submit a patch if this seems reasonable. > If you explain the use case maybe it could be considered. > 2) Do patches that add code hooks (and are probably under 10 lines) need to > go through the entire commitfest process. I guess what I am really asking is > if PG12 would be the first version such a patch could appear in or is PG11 > still a possibility? Just wondering what the policy on such stuff is. > If it is a new feature and is not in the last CF, it won't be considered for v11 (even small patches). -- Euler Taveira Timbira - http://www.timbira.com.br/ PostgreSQL: Consultoria, Desenvolvimento, Suporte 24x7 e Treinamento