ClickHouse/tests/queries/0_stateless/02245_weird_partitions_pruning.sql

-- We use a hack - partition by ignore(d1). In some cases there are two columns 
-- not fully correlated (<1) (date_begin - date_end or datetime - datetime_in_TZ_with_DST)
-- If we partition by these columns instead of one it will be twice more partitions.
-- Partition by (.., ignore(d1)) allows to partition by the first column but build 
-- min_max indexes for both column, so partition pruning works for both columns.
-- It's very similar to min_max skip index but gives bigger performance boost, 
-- because partition pruning happens on very early query stage.


DROP TABLE IF EXISTS weird_partitions_02245;

CREATE TABLE weird_partitions_02245(d DateTime, d1 DateTime default d - toIntervalHour(8), id Int64)
Engine=MergeTree
PARTITION BY (toYYYYMM(toDateTime(d)), ignore(d1))
ORDER BY id;

INSERT INTO weird_partitions_02245(d, id)
SELECT
    toDateTime('2021-12-31 22:30:00') AS d,
    number
FROM numbers(1000);

INSERT INTO weird_partitions_02245(d, id)
SELECT
    toDateTime('2022-01-01 00:30:00') AS d,
    number
FROM numbers(1000);

INSERT INTO weird_partitions_02245(d, id)
SELECT
    toDateTime('2022-01-31 22:30:00') AS d,
    number
FROM numbers(1000);

INSERT INTO weird_partitions_02245(d, id)
SELECT
    toDateTime('2023-01-31 22:30:00') AS d,
    number
FROM numbers(1000);

OPTIMIZE TABLE weird_partitions_02245;
OPTIMIZE TABLE weird_partitions_02245;

SELECT DISTINCT _partition_id, _partition_value FROM weird_partitions_02245 ORDER BY _partition_id ASC;

SELECT _partition_id, min(d), max(d), min(d1), max(d1), count() FROM weird_partitions_02245 GROUP BY _partition_id ORDER BY _partition_id ASC;

select  DISTINCT _partition_id from weird_partitions_02245 where d >= '2021-12-31 00:00:00' and d < '2022-01-01 00:00:00' ORDER BY _partition_id;
explain estimate select  DISTINCT _partition_id from weird_partitions_02245 where d >= '2021-12-31 00:00:00' and d < '2022-01-01 00:00:00';

select  DISTINCT _partition_id from weird_partitions_02245 where d >= '2022-01-01 00:00:00' and  d1 >= '2021-12-31 00:00:00' and d1 < '2022-01-01 00:00:00' ORDER BY _partition_id;;
explain estimate select  DISTINCT _partition_id from weird_partitions_02245 where d >= '2022-01-01 00:00:00' and d1 >= '2021-12-31 00:00:00' and d1 < '2022-01-01 00:00:00';

select  DISTINCT _partition_id from weird_partitions_02245 where d1 >= '2021-12-31 00:00:00' and d1 < '2022-01-01 00:00:00' ORDER BY _partition_id;;
explain estimate select  DISTINCT _partition_id from weird_partitions_02245 where d1 >= '2021-12-31 00:00:00' and d1 < '2022-01-01 00:00:00';

select  DISTINCT _partition_id from weird_partitions_02245 where d >= '2022-01-01 00:00:00' and  d1 >= '2021-12-31 00:00:00' and d1 < '2020-01-01 00:00:00' ORDER BY _partition_id;;
explain estimate select  DISTINCT _partition_id from weird_partitions_02245 where d >= '2022-01-01 00:00:00' and d1 >= '2021-12-31 00:00:00' and d1 < '2020-01-01 00:00:00';

DROP TABLE weird_partitions_02245;