On Fri, 28 Feb 2025 at 20:26, Robert Haas <robertmh...@gmail.com> wrote: > > Prior to PostgreSQL 10, EXPLAIN had just 2 options: VACUUM and > ANALYZE.
I think you meant "some time prior to PostgreSQL 10". PostgreSQL 9.0 had 5 options, of which COSTS, BUFFERS, and FORMAT were newly added, so only before 9.0 we had 2 options. PostgreSQL 9.2 then added TIMING on top of that, for a total of 6 options prior to PostgreSQL 10. > It wouldn't make sense for core to have an EXPLAIN > option whose whole purpose is to cater to the needs of some extension, > so that made me think of providing some extensibility infrastructure. +1, Neon would greatly appreciate infrastructure to allow extending EXPLAIN. > 0001 allows a loadable module to register new EXPLAIN options. > Currently, EXPLAIN (FUNGUS) will error out, but if you want to make it > work, this patch is for you. This patch also allows you to stash some > state related to your new option, or options, in the ExplainState. > Core options have hard-coded structure members; e.g. EXPLAIN (BUFFERS) > sets es->buffers. If you add EXPLAIN (FUNGUS), there won't be an > es->fungus, but you can get about the same effect using the new > facilities provided here. Does this work with parallel workers' stats? I can't seem to figure out whether or where parallel workers would pass through their extended explain statistics, mostly because of the per-backend nature of ID generation making the pointers of ExplainState->extension_state unshareable. Kind regards, Matthias van de Meent
