On Tue, Oct 11, 2022 at 09:49:14AM -0400, Tom Lane wrote: > > If you're trying to investigate custom-plan behavior, then you > need to supply concrete parameter values somewhere, so I think > this approach is fine for that case. (Shoehorning parameter > values into EXPLAIN options seems like it'd be a bit much.) > However, investigating generic-plan behavior this way is tedious, > since you have to invent irrelevant parameter values, plus mess > with plan_cache_mode or else run the explain half a dozen times. > So I can get behind having a more convenient way for that.
One common use case is tools identifying a slow query using pg_stat_statements, identifying some missing indexes and then wanting to check whether the index should be useful using some hypothetical index. FTR I'm working on such a project and for now we have to go to great lengths trying to "unjumble" such queries, so having a way to easily get the answer for a generic plan would be great.
