USE test; 
SET autocommit = 0; 
SET @a= -1; 
SET @b= -2; 
START TRANSACTION; 
CREATE TABLE IF NOT EXISTS myCity (a int, b char(20)); 
INSERT INTO myCity VALUES (1, 'Milan'); 
INSERT INTO myCity VALUES (2, 'London'); 
COMMIT; 
START TRANSACTION; 
DELETE FROM myCity; 
SET @a = (SELECT COUNT(*) FROM myCity); 
ROLLBACK; 
START TRANSACTION; 
SET @b = (SELECT COUNT(*) FROM myCity); 
START TRANSACTION; 
DROP TABLE myCity; 
SELECT (@a+@b) AS res; 
COMMIT;