mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-12-19 04:42:37 +00:00
34 lines
1.2 KiB
SQL
34 lines
1.2 KiB
SQL
SET mutations_sync = 2;
|
|
|
|
DROP TABLE IF EXISTS t_sparse_mutations_2;
|
|
|
|
CREATE TABLE t_sparse_mutations_2 (key UInt8, id UInt64, s String)
|
|
ENGINE = MergeTree ORDER BY id PARTITION BY key
|
|
SETTINGS ratio_of_defaults_for_sparse_serialization = 0.9;
|
|
|
|
INSERT INTO t_sparse_mutations_2 SELECT 1, number, toString(number) FROM numbers (10000);
|
|
|
|
SELECT type, serialization_kind FROM system.parts_columns
|
|
WHERE database = currentDatabase() AND table = 't_sparse_mutations_2' AND column = 's' AND active
|
|
ORDER BY name;
|
|
|
|
SELECT count(), sum(s::UInt64) FROM t_sparse_mutations_2 WHERE s != '';
|
|
|
|
ALTER TABLE t_sparse_mutations_2 UPDATE s = '' WHERE id % 13 != 0;
|
|
|
|
SELECT type, serialization_kind FROM system.parts_columns
|
|
WHERE database = currentDatabase() AND table = 't_sparse_mutations_2' AND column = 's' AND active
|
|
ORDER BY name;
|
|
|
|
SELECT count(), sum(s::UInt64) FROM t_sparse_mutations_2 WHERE s != '';
|
|
|
|
OPTIMIZE TABLE t_sparse_mutations_2 FINAL;
|
|
|
|
SELECT type, serialization_kind FROM system.parts_columns
|
|
WHERE database = currentDatabase() AND table = 't_sparse_mutations_2' AND column = 's' AND active
|
|
ORDER BY name;
|
|
|
|
SELECT count(), sum(s::UInt64) FROM t_sparse_mutations_2 WHERE s != '';
|
|
|
|
DROP TABLE t_sparse_mutations_2;
|