Alexander Farber wrote: > Good morning, there are these 2 records in a table: > > # select m.played, m.mid, m.action, m.gid, m.uid from words_moves m where gid=10; > played | mid | action | gid | uid > -------------------------------+-----+--------+-----+----- > 2018-02-19 14:42:08.46222+01 | 12 | play | 10 | 9 > 2018-02-20 15:06:01.430634+01 | 216 | expire | 10 | 11 > (2 rows) > > I try to get the record with the latest timestamp by adding a NOT EXISTS condition - > > # select m.played, m.mid, m.action, m.gid, m.uid from words_moves m where gid=10 > and not exists (select 1 from words_moves x where m.mid=x.mid AND x.played > m.played); > played | mid | action | gid | uid > -------------------------------+-----+--------+-----+----- > 2018-02-19 14:42:08.46222+01 | 12 | play | 10 | 9 > 2018-02-20 15:06:01.430634+01 | 216 | expire | 10 | 11 > (2 rows) > > Why are still 2 records returned? I am probably overlooking something simple, sorry... You are only checking if there is a later timestamp *for the same "mid"*. Since the two rows have different "mid", they are not compared. Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com
