On 26 February 2017 at 10:09, Sven R. Kunze <srku...@mail.de> wrote: > >>># create index docs_birthdate_idx ON docs using btree > (((meta->>'birthdate')::date)); > ERROR: functions in index expression must be marked IMMUTABLE > > So, what is the problem here? >
Date functions are inherently not immutable because of timezones. Your solution of using to_timestamp doesn't help because it automatically returns a value in WITH TIMESTAMP. Do you get anywhere by using "::timestamp without time zone" instead, as suggested here? https://www.postgresql.org/message-id/4E039D16.20704%40pinpointresearch.com Geoff
