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CREATE TABLE bug_53756 (pk INT, c1 INT) ENGINE=InnoDB;
ALTER TABLE bug_53756 ADD PRIMARY KEY (pk);
INSERT INTO bug_53756 VALUES(1, 11), (2, 22), (3, 33), (4, 44);
# Select a less restrictive isolation level.
SET GLOBAL TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
COMMIT;
# Start a transaction in the default connection for isolation.
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
SELECT * FROM bug_53756;
pk c1
1 11
2 22
3 33
4 44
connect con1,localhost,root,,;
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
DELETE FROM bug_53756 WHERE pk=1;
connect con2,localhost,root,,;
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
DELETE FROM bug_53756 WHERE pk=2;
connect con3,localhost,root,,;
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
UPDATE bug_53756 SET c1=77 WHERE pk=3;
connect con4,localhost,root,,;
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
UPDATE bug_53756 SET c1=88 WHERE pk=4;
connect con5,localhost,root,,;
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
INSERT INTO bug_53756 VALUES(5, 55);
connect con6,localhost,root,,;
START TRANSACTION;
SELECT @@tx_isolation;
@@tx_isolation
READ-COMMITTED
INSERT INTO bug_53756 VALUES(6, 66);
connection con1;
COMMIT;
connection con3;
COMMIT;
connection con4;
ROLLBACK;
connection con6;
ROLLBACK;
# The connections 2 and 5 stay open.
# Delete of row 1 was committed.
# Update of row 3 was committed.
# Due to isolation level read committed, these should be included.
# All other changes should not be included.
connection default;
SELECT * FROM bug_53756;
pk c1
2 22
3 77
4 44
START TRANSACTION;
INSERT INTO bug_53756 VALUES (666,666);
# restart
disconnect con1;
disconnect con2;
disconnect con3;
disconnect con4;
disconnect con5;
disconnect con6;
#
# Select recovered data.
# Delete of row 1 was committed.
# Update of row 3 was committed.
# These should be included.
# All other changes should not be included.
# Delete of row 2 and insert of row 5 should be rolled back
SELECT * FROM bug_53756;
pk c1
2 22
3 77
4 44
DROP TABLE bug_53756;
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