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-----------------------------------------------------------------------
- Locking issues case 5:
- Deleting primary key
- using READ COMMITTED transaction isolation level
-----------------------------------------------------------------------
DROP TABLE IF EXISTS t0;
CREATE TABLE t0(id INT AUTO_INCREMENT PRIMARY KEY, value INT);
Inserting 200,000 rows
UPDATE t0 SET value=100 WHERE id=190000;
connect con1,localhost,root,,;
connect con2,localhost,root,,;
connection con1;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
BEGIN;
SELECT * FROM t0 WHERE value > 0 FOR UPDATE;
connection con2;
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
BEGIN;
DELETE FROM t0 WHERE id=190000;
COMMIT;
connection con1;
id value
ERROR: 0
COMMIT;
connection default;
disconnect con1;
disconnect con2;
DROP TABLE t0;
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