mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-25 17:12:03 +00:00
42 lines
1.7 KiB
MySQL
42 lines
1.7 KiB
MySQL
|
-- There is different code path when:
|
||
|
-- - _state is not requested
|
||
|
-- - _state is requested
|
||
|
-- - only _state is requested
|
||
|
SELECT * FROM system.parts FORMAT Null;
|
||
|
SELECT *, _state FROM system.parts FORMAT Null;
|
||
|
SELECT _state FROM system.parts FORMAT Null;
|
||
|
|
||
|
-- Create one table and see some columns in system.parts
|
||
|
DROP TABLE IF EXISTS data_01660;
|
||
|
CREATE TABLE data_01660 (key Int) Engine=MergeTree() ORDER BY key;
|
||
|
SYSTEM STOP MERGES data_01660;
|
||
|
|
||
|
-- Empty
|
||
|
SELECT _state FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
SELECT name, _state FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
SELECT name, active FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
|
||
|
-- Add part and check again
|
||
|
SELECT '# two parts';
|
||
|
INSERT INTO data_01660 VALUES (0);
|
||
|
INSERT INTO data_01660 VALUES (1);
|
||
|
SELECT _state FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
SELECT name, _state FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
SELECT name, active FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
|
||
|
-- OPTIMIZE to create Outdated parts
|
||
|
SELECT '# optimize';
|
||
|
SYSTEM START MERGES data_01660;
|
||
|
OPTIMIZE TABLE data_01660 FINAL;
|
||
|
SELECT count(), _state FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660' GROUP BY _state;
|
||
|
|
||
|
-- TRUNCATE does not remove parts instantly
|
||
|
SELECT '# truncate';
|
||
|
TRUNCATE data_01660;
|
||
|
SELECT _state FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|
||
|
|
||
|
-- But DROP does
|
||
|
SELECT '# drop';
|
||
|
DROP TABLE data_01660;
|
||
|
SELECT * FROM system.parts WHERE database = currentDatabase() AND table = 'data_01660';
|