At Wed, 12 May 2021 20:36:18 -0400, Bruce Momjian <br...@momjian.us> wrote in > On Wed, May 12, 2021 at 05:51:49PM +0800, Julien Rouhaud wrote: > > On Wed, May 12, 2021 at 11:42:12AM +0200, Pavel Stehule wrote: > > > this check just can check if there is "any" query-id provider. In this > > > context is not important if it is buildin or external > > > > Yes, the idea is that if you execute "SELECT * FROM pg_stat_statements" or > > similar, then if the executing query itself doesn't have a queryid then > > it's very likely that you didn't configure compute_query_id or an > > alternative > > query_id implementation properly. And loudly complaining seems like the > > right > > thing to do. > > I understand the desire to make pg_stat_statements require minimal > configuration, but frankly, if the server-side variable query id API is > confusing, I think we have done more harm than good. > > The problem with compute_query_id=auto is that there is no way to know > if the query id is actually enabled, unless you guess from the installed > extensions, or we add another variable to report that, and maybe another > variable to control the provier, unless we require turning > compute_query_id=off if you are using custom query id computation. What > if it is auto, and pg_stat_statments is installed, and you want to use a > custom query id computation --- what happens? As you can see, this is > all becoming very complicated. > > I think we might be just as well to go with compute_query_id=on/off, and > just complain loudly from CREATE EXTENSION, or in the server logs on > server start via shared_preload_libraries, or when querying > pg_stat_statements system view. We simply say to change > compute_query_id=on or to provide a custom query id implementation.
FWIW, I personally am fine with that (ignoring details :p), that is, leaving the whole responsibility of a sane setup to users. If we are going to automate even a part of it, I think we need to make it perfect at least to a certain level. The current auery_id = auto looks like somewhat halfway, or narrow-ranged. regards. -- Kyotaro Horiguchi NTT Open Source Software Center
