Will Hartung schrieb am 31.05.2019 um 00:11: > If you have 10M rows with a “STATUS” column of 1 or 2, and an index > on that column, then you have a 2 node index with a bazillion row > pointers. Some systems (I can’t speak to PG in this regard) > degenerate in this kind of use case since the index is more or less > designed to work great in unique identifiers than low cardinality > values. The representation of large record pointer lists may just not > be handled well as edge cases.
What I very often do in theses cases is to create two partial indexes: One with "WHERE status = 1" and another with "WHERE STATUS = 2" including _another_ column in the index that I usually use together with the status column in the queries.
