Mark Steben <mark.steben@xxxxxxxxxxxxxxxxx> writes: > We are currently running postgres version 12.2. I have a query that uses > regexp code to confirm if a text field is a date or not. It is resource > intensive and long running. I have made a regexp index (actually several > flavors of regexp indexes) to aid in this queries performance. However I > cannot seem to 'convince' the planner to use the indexes I create. I don't understand your complaint. Your example shows that it *is* using the index: > -> Bitmap Index Scan on custattr_value (cost=0.00..9787.64 rows=479041 width=0) > Finally if I remove the 'ca.account_id is not null' expression > [ it doesn't use the index ] Well, of course not, because then the query doesn't match the index's WHERE condition (i.e., there could be rows the query needs to return that are not included in the index). But I imagine that restriction isn't very selective, so you could probably omit it from the index definition as well; then the index would work for queries with or without that restriction. regards, tom lane
