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connect cancel_purge,localhost,root,,;
START TRANSACTION WITH CONSISTENT SNAPSHOT;
connection default;
CREATE TABLE t (a int PRIMARY KEY, b int) engine = InnoDB;
CREATE TABLE t2 (a int PRIMARY KEY) engine = InnoDB;
INSERT INTO t VALUES (10, 10), (20, 20), (30, 30);
INSERT INTO t2 VALUES (10), (20), (30);
BEGIN;
SELECT * FROM t WHERE a = 20 FOR UPDATE;
a b
20 20
connect con_2,localhost,root,,;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
BEGIN;
SET DEBUG_SYNC = 'lock_trx_handle_wait_enter SIGNAL upd_locked WAIT_FOR upd_cont EXECUTE 2';
UPDATE t SET b = 100;
connect con_3,localhost,root,,;
BEGIN;
UPDATE t2 SET a = a + 100;
SELECT * FROM t WHERE a = 30 FOR UPDATE;
a b
30 30
SET DEBUG_SYNC='now WAIT_FOR upd_locked';
SET DEBUG_SYNC = 'lock_wait_start SIGNAL sel_locked';
SELECT * FROM t WHERE a = 20 FOR UPDATE;
connection default;
SET DEBUG_SYNC='now WAIT_FOR sel_locked';
ROLLBACK;
SET DEBUG_SYNC='now SIGNAL upd_cont';
SET DEBUG_SYNC="now WAIT_FOR upd_locked";
SET SESSION innodb_lock_wait_timeout=1;
SELECT * FROM t WHERE a = 10 FOR UPDATE;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
SET DEBUG_SYNC="now SIGNAL upd_cont";
connection con_3;
a b
20 20
connection con_2;
ERROR 40001: Deadlock found when trying to get lock; try restarting transaction
disconnect con_3;
disconnect con_2;
connection default;
SET DEBUG_SYNC = 'RESET';
DROP TABLE t;
DROP TABLE t2;
disconnect cancel_purge;
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