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CREATE TABLE t(a INT PRIMARY KEY, b INT, c INT, UNIQUE KEY `b_c` (`b`,`c`))
ENGINE=InnoDB, STATS_PERSISTENT=0;
INSERT INTO t SET a = 1, c = 2;
connect con1,localhost,root;
BEGIN;
INSERT INTO t SET a=2, c=2;
connection default;
BEGIN;
SET DEBUG_SYNC="lock_wait_start SIGNAL select_locked";
SELECT * FROM t FORCE INDEX(b) FOR UPDATE;
connection con1;
SET DEBUG_SYNC="now WAIT_FOR select_locked";
ROLLBACK;
connection default;
# If the bug is not fixed, and the both unique index key fields are
# NULL, there will be two (1, NULL, 2) rows in the result,
# because cursor will be restored to (NULL, 2, 1) position for
# secondary key instead of "supremum".
a b c
1 NULL 2
COMMIT;
SET DEBUG_SYNC="RESET";
disconnect con1;
DROP TABLE t;
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