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DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (a <INT_COLUMN>, b <CHAR_COLUMN>) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
INSERT INTO t1 (a,b) VALUES (1,'a'),(2,'b'),(3,'c'),(4,'d'),(5,'e'),(10000,'foobar');
INSERT INTO t1 (a,b) SELECT a, b FROM t1;
UPDATE t1 SET a=a+100;
SELECT a,b FROM t1;
a b
101 a
101 a
10100 foobar
10100 foobar
102 b
102 b
103 c
103 c
104 d
104 d
105 e
105 e
UPDATE t1 SET a=a-100, b=DEFAULT WHERE a>100;
SELECT a,b FROM t1;
a b
1 NULL
1 NULL
10000 NULL
10000 NULL
2 NULL
2 NULL
3 NULL
3 NULL
4 NULL
4 NULL
5 NULL
5 NULL
UPDATE t1 SET b = 'update' WHERE a <= 4 ORDER BY b DESC, a ASC LIMIT 1;
SELECT a,b FROM t1;
a b
1 NULL
1 update
10000 NULL
10000 NULL
2 NULL
2 NULL
3 NULL
3 NULL
4 NULL
4 NULL
5 NULL
5 NULL
DROP TABLE t1;
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