1drop table if exists t1; 2CREATE TABLE t1 (data LONGBLOB) ENGINE=myisam; 3INSERT INTO t1 (data) VALUES (NULL); 4UPDATE t1 set data=repeat('a',18*1024*1024); 5select length(data) from t1; 6length(data) 718874368 8delete from t1 where left(data,1)='a'; 9check table t1; 10Table Op Msg_type Msg_text 11test.t1 check status OK 12truncate table t1; 13INSERT INTO t1 (data) VALUES (repeat('a',1*1024*1024)); 14INSERT INTO t1 (data) VALUES (repeat('b',16*1024*1024-1024)); 15delete from t1 where left(data,1)='b'; 16check table t1; 17Table Op Msg_type Msg_text 18test.t1 check status OK 19UPDATE t1 set data=repeat('c',17*1024*1024); 20check table t1; 21Table Op Msg_type Msg_text 22test.t1 check status OK 23delete from t1 where left(data,1)='c'; 24check table t1; 25Table Op Msg_type Msg_text 26test.t1 check status OK 27INSERT INTO t1 set data=repeat('a',18*1024*1024); 28select length(data) from t1; 29length(data) 3018874368 31SET STATEMENT sql_mode = 'NO_ENGINE_SUBSTITUTION' FOR 32alter table t1 modify data blob; 33Warnings: 34Warning 1265 Data truncated for column 'data' at row 1 35select length(data) from t1; 36length(data) 3765535 38drop table t1; 39CREATE TABLE t1 (data BLOB) ENGINE=myisam; 40INSERT INTO t1 (data) VALUES (NULL); 41UPDATE IGNORE t1 set data=repeat('a',18*1024*1024); 42Warnings: 43Warning 1265 Data truncated for column 'data' at row 1 44select length(data) from t1; 45length(data) 4665535 47drop table t1; 48