drop table if exists t1,t2,t7,t8,t9; drop database if exists mysqltest; create table t1 (a int not null auto_increment, b char(16) not null, primary key (a)); create table t2 (a int not null auto_increment, b char(16) not null, primary key (a)); insert into t1 (b) values ("test"),("test1"),("test2"),("test3"); insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; insert into t2 (b) select b from t1; insert into t1 (b) select b from t2; drop table t2; insert into t9 select * from t1; check table t9; Table Op Msg_type Msg_text test.t9 check status OK optimize table t9; Table Op Msg_type Msg_text test.t9 optimize status OK repair table t9; Table Op Msg_type Msg_text test.t9 repair status OK alter table t9 add column c int not null; show create table t9; Table Create Table t9 CREATE TABLE `t9` ( `a` int(11) NOT NULL auto_increment, `b` char(16) NOT NULL default '', `c` int(11) NOT NULL default '0', PRIMARY KEY (`a`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 DATA DIRECTORY='TEST_DIR/var/tmp/' INDEX DIRECTORY='TEST_DIR/var/run/' alter table t9 rename t8, add column d int not null; alter table t8 rename t7; rename table t7 to t9; drop table t1; Got one of the listed errors Got one of the listed errors Got one of the listed errors Got one of the listed errors Got one of the listed errors alter table t9 rename mysqltest.t9; select count(*) from mysqltest.t9; count(*) 16724 show create table mysqltest.t9; Table Create Table t9 CREATE TABLE `t9` ( `a` int(11) NOT NULL auto_increment, `b` char(16) NOT NULL default '', `c` int(11) NOT NULL default '0', `d` int(11) NOT NULL default '0', PRIMARY KEY (`a`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 DATA DIRECTORY='TEST_DIR/var/tmp/' INDEX DIRECTORY='TEST_DIR/var/run/' drop database mysqltest; create table t1 (a int not null) engine=myisam; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) NOT NULL default '0' ) ENGINE=MyISAM DEFAULT CHARSET=latin1 alter table t1 add b int; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) NOT NULL default '0', `b` int(11) default NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) NOT NULL default '0', `b` int(11) default NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 drop table t1;