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--source include/count_sessions.inc
--source include/have_debug_sync.inc
CREATE TABLE t1 (id INT PRIMARY KEY);
INSERT INTO t1 VALUES (1);
--connect (con1, localhost, root,,)
--connect (con2, localhost, root,,)
--connect (con3, localhost, root,,)
--connection con3
# create a read view which will prevent purging the id=1
BEGIN;
SELECT * FROM t1;
--connection con1
# delete-mark the id=1
DELETE FROM t1 WHERE id=1;
# place LOCK_S
BEGIN;
SELECT * FROM t1 FOR SHARE;
--connection con2
# place a WAITING LOCK_X
BEGIN;
SET DEBUG_SYNC = "lock_wait_will_wait SIGNAL con2_will_wait";
--send SELECT * FROM t1 FOR UPDATE
--connection con1
SET DEBUG_SYNC = "now WAIT_FOR con2_will_wait";
# attempt S to X escalation, bypassing con2, and using implicit lock
INSERT INTO t1 VALUES (1);
--connection con3
# insert a record just before id=1, just to trigger validation for this record
SET DEBUG_SYNC = "lock_wait_will_wait SIGNAL con3_will_wait";
--send INSERT INTO t1 VALUES (0)
--connection con1
SET DEBUG_SYNC = "now WAIT_FOR con3_will_wait";
--connection default
--disconnect con1
--disconnect con2
--disconnect con3
DROP TABLE t1;
--source include/wait_until_count_sessions.inc
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