CREATE TABLE t1(a INT); INSERT INTO t1 VALUES(1),(2); DELETE FROM t1 WHERE a=1; OPTIMIZE TABLE t1; Table Op Msg_type Msg_text test.t1 optimize status OK CHECK TABLE t1; Table Op Msg_type Msg_text test.t1 check status OK DROP TABLE t1; create table t1 (v varchar(10), c char(10), t text, key(v), key(c), key(t(10))); insert into t1 (v) select concat(char(ascii('a')+s2.seq),repeat(' ',s1.seq)) from seq_0_to_9 as s1, seq_0_to_26 as s2; update t1 set c=v, t=v; select sql_big_result t,count(t) from t1 group by t limit 10; t count(t) a 10 b 10 c 10 d 10 e 10 f 10 g 10 h 10 i 10 j 10 drop table t1; set global binlog_cache_size=8192; connect con1, localhost, root; create table t1 (a text) engine=innodb; start transaction; insert t1 select repeat(seq, 1000) from seq_1_to_15; commit; start transaction; insert t1 select repeat(seq, 1000) from seq_1_to_8; commit; drop table t1; disconnect con1; connect con2, localhost, root; create table t1 (a text) engine=innodb; start transaction; insert t1 select repeat(seq, 1000) from seq_1_to_15; savepoint foo; insert t1 select repeat(seq, 1000) from seq_16_to_30; rollback to savepoint foo; insert t1 select repeat(seq, 1000) from seq_31_to_40; commit; drop table t1; disconnect con2; connection default; set global binlog_cache_size=default;