1CREATE TABLE t1 ( a INT NOT NULL, b INT NOT NULL) ; 2INSERT INTO t1 SELECT seq,seq FROM seq_1_to_2097152; 3ALTER TABLE t1 ADD INDEX i1(a); 4DELETE FROM t1 WHERE a > 2000000; 5CREATE TABLE t2 LIKE t1; 6INSERT INTO t2 SELECT * FROM t1; 7SELECT 't2 rows before small delete', COUNT(*) FROM t1; 8t2 rows before small delete COUNT(*) 9t2 rows before small delete 2000000 10DELETE t1,t2 FROM t1,t2 WHERE t1.b=t2.a AND t1.a < 2; 11SELECT 't2 rows after small delete', COUNT(*) FROM t2; 12t2 rows after small delete COUNT(*) 13t2 rows after small delete 1999999 14SELECT 't1 rows after small delete', COUNT(*) FROM t1; 15t1 rows after small delete COUNT(*) 16t1 rows after small delete 1999999 17DELETE t1,t2 FROM t1,t2 WHERE t1.b=t2.a AND t1.a < 100*1000; 18SELECT 't2 rows after big delete', COUNT(*) FROM t2; 19t2 rows after big delete COUNT(*) 20t2 rows after big delete 1900001 21SELECT 't1 rows after big delete', COUNT(*) FROM t1; 22t1 rows after big delete COUNT(*) 23t1 rows after big delete 1900001 24DROP TABLE t1,t2; 25