On Tue, Mar 27, 2018 at 03:14:30PM +0100, Glenn Pierce wrote: > Hi I am having terrible trouble with a simple partitioned table. > Select queries are very slow. .... > The child tables are all like > Check constraints: > "sensor_values_2018q1_timestamp_check" CHECK (ts >= '2018-01-01 > 00:00:00+00'::timestamp with time zone AND ts < '2018-04-01 > 01:00:00+01'::timestamp with time zone) > EXPLAIN (ANALYZE, BUFFERS) SELECT ts::timestamptz, s1.sensor_id, s1.value > FROM sensor_values s1 > WHERE s1.sensor_id = > ANY(ARRAY[596304,597992,610978,597998]) > AND s1.ts >= '2000-01-01 > 00:01:01'::timestamptz AND > s1.ts < '2018-03-20 > 00:01:01'::timestamptz > Shows the following output > https://explain.depesz.com/s/c8HU It's scanning all partitions, so apparently constraint_exclusion isn't working. Is it because the CHECK has ts with different timezones +00 and +01 ?? Also, it looks funny to use 00:01:01 as the beginning of the day (although I think it's true that an HR department would understand that better..). Justin
