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-----------------------------------------------------------------------
- Locking issues case 2:
- Rows that are scanned but do not match the WHERE are not locked
- using READ COMMITTED transaction isolation level unless
- rocksdb_lock_scanned_rows is on
-----------------------------------------------------------------------
DROP TABLE IF EXISTS t0;
SELECT @@global.rocksdb_lock_scanned_rows;
@@global.rocksdb_lock_scanned_rows
0
CREATE TABLE t0(id INT PRIMARY KEY, value INT);
INSERT INTO t0 VALUES (1,0), (2,1), (3,0), (4,0), (5,1);
connect con1,localhost,root,,;
connect con2,localhost,root,,;
connection con1;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
BEGIN;
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
BEGIN;
connection con1;
SELECT * FROM t0 WHERE value > 0 FOR UPDATE;
id value
2 1
5 1
connection con2;
UPDATE t0 SET VALUE=10 WHERE id=1;
UPDATE t0 SET VALUE=10 WHERE id=5;
ERROR HY000: Lock wait timeout exceeded; try restarting transaction
connection con1;
UPDATE t0 SET value=100 WHERE id in (4,5) and value>0;
connection con2;
SELECT * FROM t0 WHERE id=4 FOR UPDATE;
id value
4 0
COMMIT;
SELECT * FROM t0;
id value
1 10
2 1
3 0
4 0
5 1
connection con1;
COMMIT;
connection default;
disconnect con1;
disconnect con2;
DROP TABLE t0;
|
