It is an expected behavior. You can see the list of array operators with which a GIN index can be used in the doc:
https://www.postgresql.org/docs/current/indexes-types.html And a very good and detailed explanation about any operator here: https://stackoverflow.com/questions/4058731/can-postgresql-index-array-columns/29245753#29245753 Regards, Flo On Wed, Mar 13, 2019 at 2:44 AM Corey Huinker <corey.huin...@gmail.com> wrote: > A client had an issue with a where that had a where clause something like > this: > > WHERE 123456 = ANY(integer_array_column) > > > I was surprised that this didn't use the pre-existing GIN index on > integer_array_column, whereas recoding as > > WHERE ARRAY[123456] <@ integer_array_column > > > did cause the GIN index to be used. Is this a known/expected behavior? If > so, is there any logical reason why we couldn't have the planner pick up on > that? >
