Andres Freund <and...@anarazel.de> writes: > On 2018-06-18 18:05:11 -0400, Tom Lane wrote: >> Well, what I was thinking about was that this functionality already >> exists (I think) in one or more "index advisor" plugins.
> They're doing the opposite, right? I.e. they return "hypothetical > indexes", which then can be used by the planner. None of the ones I've > seen currently mask out an existing index. I had the idea that some of them could also hide existing indexes. It's been awhile, so maybe my memory is faulty, but the hook we provide is capable of that: /* * Allow a plugin to editorialize on the info we obtained from the * catalogs. Actions might include altering the assumed relation size, * removing an index, or adding a hypothetical index to the indexlist. */ if (get_relation_info_hook) (*get_relation_info_hook) (root, relationObjectId, inhparent, rel); regards, tom lane