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#
# MDEV-26642 Weird SELECT view when a record is
# modified to the same value by two transactions
# MDEV-32898 Phantom rows caused by updates of PRIMARY KEY
#
CREATE TABLE t(a INT PRIMARY KEY, b INT) ENGINE=InnoDB;
INSERT INTO t VALUES (1,1),(2,2);
BEGIN;
SELECT * FROM t LOCK IN SHARE MODE;
a b
1 1
2 2
connect con_weird,localhost,root;
BEGIN;
SELECT * FROM t;
a b
1 1
2 2
connect consistent,localhost,root;
SET innodb_snapshot_isolation=ON;
BEGIN;
SELECT * FROM t;
a b
1 1
2 2
connection default;
UPDATE t SET a=3 WHERE b=2;
COMMIT;
connection consistent;
UPDATE t SET b=3;
ERROR HY000: Record has changed since last read in table 't'
SELECT * FROM t;
a b
1 1
3 2
COMMIT;
connection con_weird;
UPDATE t SET b=3;
SELECT * FROM t;
a b
1 3
2 2
3 3
COMMIT;
connection default;
SELECT * FROM t;
a b
1 3
3 3
DROP TABLE t;
#
# MDEV-26643 Inconsistent behaviors of UPDATE under
# READ UNCOMMITTED and READ COMMITTED isolation level
#
CREATE TABLE t(a INT, b INT) ENGINE=InnoDB;
INSERT INTO t VALUES(NULL, 1), (2, 2);
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
BEGIN;
UPDATE t SET a = 10;
connection consistent;
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
UPDATE t SET b = 20 WHERE a;
connection default;
COMMIT;
connection consistent;
SELECT * FROM t;
a b
10 20
10 20
connection default;
TRUNCATE TABLE t;
INSERT INTO t VALUES(NULL, 1), (2, 2);
BEGIN;
UPDATE t SET a = 10;
connection consistent;
SET TRANSACTION ISOLATION LEVEL READ COMMITTED;
UPDATE t SET b = 20 WHERE a;
connection default;
COMMIT;
connection consistent;
SELECT * FROM t;
a b
10 20
10 20
connection default;
TRUNCATE TABLE t;
INSERT INTO t VALUES(NULL, 1), (2, 2);
BEGIN;
UPDATE t SET a = 10;
connection con_weird;
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
UPDATE t SET b = 20 WHERE a;
connection default;
SELECT * FROM t;
a b
10 1
10 2
COMMIT;
connection con_weird;
COMMIT;
connection default;
SELECT * FROM t;
a b
10 1
10 20
DROP TABLE t;
#
# MDEV-33802 Weird read view after ROLLBACK of other transactions
#
CREATE TABLE t(a INT PRIMARY KEY, b INT UNIQUE) ENGINE=InnoDB;
INSERT INTO t SET a=1;
BEGIN;
INSERT INTO t SET a=2;
connection consistent;
START TRANSACTION WITH CONSISTENT SNAPSHOT;
SELECT * FROM t FORCE INDEX (b) FOR UPDATE;
ERROR HY000: Record has changed since last read in table 't'
connection con_weird;
START TRANSACTION WITH CONSISTENT SNAPSHOT;
SELECT * FROM t FORCE INDEX (b) FOR UPDATE;
connection default;
ROLLBACK;
connection con_weird;
a b
1 NULL
SELECT * FROM t FORCE INDEX (b) FOR UPDATE;
a b
1 NULL
disconnect con_weird;
connection consistent;
SELECT * FROM t FORCE INDEX (b) FOR UPDATE;
a b
1 NULL
disconnect consistent;
connection default;
DROP TABLE t;
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