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;
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
DROP TABLE t1;