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DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (a INT, b INT, c INT, UNIQUE (A), UNIQUE(B));
INSERT t1 VALUES (1,2,10), (3,4,20);
INSERT t1 VALUES (5,6,30) ON DUPLICATE KEY UPDATE c=c+100;
SELECT * FROM t1;
a b c
1 2 10
3 4 20
5 6 30
INSERT t1 VALUES (5,7,40) ON DUPLICATE KEY UPDATE c=c+100;
SELECT * FROM t1;
a b c
1 2 10
3 4 20
5 6 130
INSERT t1 VALUES (8,4,50) ON DUPLICATE KEY UPDATE c=c+1000;
SELECT * FROM t1;
a b c
1 2 10
3 4 1020
5 6 130
INSERT t1 VALUES (1,4,60) ON DUPLICATE KEY UPDATE c=c+10000;
SELECT * FROM t1;
a b c
1 2 10010
3 4 1020
5 6 130
INSERT t1 VALUES (1,9,70) ON DUPLICATE KEY UPDATE c=c+100000, b=4;
ERROR 23000: Duplicate entry '4' for key 2
SELECT * FROM t1;
a b c
1 2 10010
3 4 1020
5 6 130
TRUNCATE TABLE t1;
INSERT t1 VALUES (1,2,10), (3,4,20);
INSERT t1 VALUES (5,6,30), (7,4,40), (8,9,60) ON DUPLICATE KEY UPDATE c=c+100;
SELECT * FROM t1;
a b c
1 2 10
3 4 120
5 6 30
8 9 60
INSERT t1 SET a=5 ON DUPLICATE KEY UPDATE b=0;
SELECT * FROM t1;
a b c
1 2 10
3 4 120
5 0 30
8 9 60
INSERT t1 VALUES (2,1,11), (7,4,40) ON DUPLICATE KEY UPDATE c=c+VALUES(a);
SELECT *, VALUES(a) FROM t1;
a b c VALUES(a)
1 2 10 NULL
3 4 127 NULL
5 0 30 NULL
8 9 60 NULL
2 1 11 NULL
explain extended SELECT *, VALUES(a) FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 5
Warnings:
Note 1003 select high_priority test.t1.a AS `a`,test.t1.b AS `b`,test.t1.c AS `c`,values(test.t1.a) AS `VALUES(a)` from test.t1
explain extended select * from t1 where values(a);
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
Warnings:
Note 1003 select high_priority test.t1.a AS `a`,test.t1.b AS `b`,test.t1.c AS `c` from test.t1
DROP TABLE t1;
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