mirror of
https://github.com/ClickHouse/ClickHouse.git
synced 2024-11-14 03:25:15 +00:00
27 lines
968 B
SQL
27 lines
968 B
SQL
select '--------';
|
|
SELECT arrayJoin([0, 1, 3, NULL]) AS x, x = 0, if(x = 0, 'x=0', 'x<>0') ORDER BY x;
|
|
|
|
select '--------';
|
|
drop table if exists mutation_delete_null_rows;
|
|
|
|
CREATE TABLE mutation_delete_null_rows
|
|
(
|
|
`EventDate` Date,
|
|
`CounterID` Nullable(String),
|
|
`UserID` Nullable(UInt32)
|
|
)
|
|
ENGINE = MergeTree()
|
|
ORDER BY EventDate;
|
|
|
|
INSERT INTO mutation_delete_null_rows VALUES ('2020-01-01', '', 2)('2020-01-02', 'aaa', 0);
|
|
INSERT INTO mutation_delete_null_rows VALUES ('2020-01-03', '', 2)('2020-01-04', '', 2)('2020-01-05', NULL, 2)('2020-01-06', 'aaa', 0)('2020-01-07', 'aaa', 0)('2020-01-08', 'aaa', NULL);
|
|
|
|
SELECT *,UserID = 0 as UserIDEquals0, if(UserID = 0, 'delete', 'leave') as verdict FROM mutation_delete_null_rows ORDER BY EventDate;
|
|
|
|
ALTER TABLE mutation_delete_null_rows DELETE WHERE UserID = 0 SETTINGS mutations_sync=1;
|
|
|
|
select '--------';
|
|
SELECT * FROM mutation_delete_null_rows ORDER BY EventDate;
|
|
|
|
drop table mutation_delete_null_rows;
|