drop table if exists t1,t2; drop database if exists mysqltest; create table t1 ( col1 int not null auto_increment primary key, col2 varchar(30) not null, col3 varchar (20) not null, col4 varchar(4) not null, col5 enum('PENDING', 'ACTIVE', 'DISABLED') not null, col6 int not null, to_be_deleted int); insert into t1 values (2,4,3,5,"PENDING",1,7); alter table t1 add column col4_5 varchar(20) not null after col4, add column col7 varchar(30) not null after col5, add column col8 datetime not null, drop column to_be_deleted, change column col2 fourth varchar(30) not null after col3, modify column col6 int not null first; select * from t1; col6 col1 col3 fourth col4 col4_5 col5 col7 col8 1 2 3 4 5 PENDING 0000-00-00 00:00:00 drop table t1; create table t1 (bandID MEDIUMINT UNSIGNED NOT NULL PRIMARY KEY, payoutID SMALLINT UNSIGNED NOT NULL); insert into t1 (bandID,payoutID) VALUES (1,6),(2,6),(3,4),(4,9),(5,10),(6,1),(7,12),(8,12); alter table t1 add column new_col int, order by payoutid,bandid; select * from t1; bandID payoutID new_col 6 1 NULL 3 4 NULL 1 6 NULL 2 6 NULL 4 9 NULL 5 10 NULL 7 12 NULL 8 12 NULL alter table t1 order by bandid,payoutid; select * from t1; bandID payoutID new_col 1 6 NULL 2 6 NULL 3 4 NULL 4 9 NULL 5 10 NULL 6 1 NULL 7 12 NULL 8 12 NULL drop table t1; CREATE TABLE t1 ( GROUP_ID int(10) unsigned DEFAULT '0' NOT NULL, LANG_ID smallint(5) unsigned DEFAULT '0' NOT NULL, NAME varchar(80) DEFAULT '' NOT NULL, PRIMARY KEY (GROUP_ID,LANG_ID), KEY NAME (NAME)); ALTER TABLE t1 CHANGE NAME NAME CHAR(80) not null; SHOW FULL COLUMNS FROM t1; Field Type Collation Null Key Default Extra Privileges Comment GROUP_ID int(10) unsigned NULL NO PRI 0 # LANG_ID smallint(5) unsigned NULL NO PRI 0 # NAME char(80) latin1_swedish_ci NO MUL NULL # DROP TABLE t1; create table t1 (n int); insert into t1 values(9),(3),(12),(10); alter table t1 order by n; select * from t1; n 3 9 10 12 drop table t1; CREATE TABLE t1 ( id int(11) unsigned NOT NULL default '0', category_id tinyint(4) unsigned NOT NULL default '0', type_id tinyint(4) unsigned NOT NULL default '0', body text NOT NULL, user_id int(11) unsigned NOT NULL default '0', status enum('new','old') NOT NULL default 'new', PRIMARY KEY (id) ) ENGINE=MyISAM; ALTER TABLE t1 ORDER BY t1.id, t1.status, t1.type_id, t1.user_id, t1.body; DROP TABLE t1; CREATE TABLE t1 (AnamneseId int(10) unsigned NOT NULL auto_increment,B BLOB,PRIMARY KEY (AnamneseId)) engine=myisam; insert into t1 values (null,"hello"); LOCK TABLES t1 WRITE; ALTER TABLE t1 ADD Column new_col int not null; UNLOCK TABLES; OPTIMIZE TABLE t1; Table Op Msg_type Msg_text test.t1 optimize status OK DROP TABLE t1; create table t1 (i int unsigned not null auto_increment primary key); insert into t1 values (null),(null),(null),(null); alter table t1 drop i,add i int unsigned not null auto_increment, drop primary key, add primary key (i); select * from t1; i 1 2 3 4 drop table t1; create table t1 (name char(15)); insert into t1 (name) values ("current"); create database mysqltest; create table mysqltest.t1 (name char(15)); insert into mysqltest.t1 (name) values ("mysqltest"); select * from t1; name current select * from mysqltest.t1; name mysqltest alter table t1 rename mysqltest.t1; ERROR 42S01: Table 't1' already exists select * from t1; name current select * from mysqltest.t1; name mysqltest drop table t1; drop database mysqltest; create table t1 (n1 int not null, n2 int, n3 int, n4 float, unique(n1), key (n1, n2, n3, n4), key (n2, n3, n4, n1), key (n3, n4, n1, n2), key (n4, n1, n2, n3) ); alter table t1 disable keys; show keys from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 n1 1 n1 A 0 NULL NULL BTREE t1 1 n1_2 1 n1 A NULL NULL NULL BTREE disabled t1 1 n1_2 2 n2 A NULL NULL NULL YES BTREE disabled t1 1 n1_2 3 n3 A NULL NULL NULL YES BTREE disabled t1 1 n1_2 4 n4 A NULL NULL NULL YES BTREE disabled t1 1 n2 1 n2 A NULL NULL NULL YES BTREE disabled t1 1 n2 2 n3 A NULL NULL NULL YES BTREE disabled t1 1 n2 3 n4 A NULL NULL NULL YES BTREE disabled t1 1 n2 4 n1 A NULL NULL NULL BTREE disabled t1 1 n3 1 n3 A NULL NULL NULL YES BTREE disabled t1 1 n3 2 n4 A NULL NULL NULL YES BTREE disabled t1 1 n3 3 n1 A NULL NULL NULL BTREE disabled t1 1 n3 4 n2 A NULL NULL NULL YES BTREE disabled t1 1 n4 1 n4 A NULL NULL NULL YES BTREE disabled t1 1 n4 2 n1 A NULL NULL NULL BTREE disabled t1 1 n4 3 n2 A NULL NULL NULL YES BTREE disabled t1 1 n4 4 n3 A NULL NULL NULL YES BTREE disabled alter table t1 enable keys; show keys from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 n1 1 n1 A 10 NULL NULL BTREE t1 1 n1_2 1 n1 A 10 NULL NULL BTREE t1 1 n1_2 2 n2 A 10 NULL NULL YES BTREE t1 1 n1_2 3 n3 A 10 NULL NULL YES BTREE t1 1 n1_2 4 n4 A 10 NULL NULL YES BTREE t1 1 n2 1 n2 A 10 NULL NULL YES BTREE t1 1 n2 2 n3 A 10 NULL NULL YES BTREE t1 1 n2 3 n4 A 10 NULL NULL YES BTREE t1 1 n2 4 n1 A 10 NULL NULL BTREE t1 1 n3 1 n3 A 10 NULL NULL YES BTREE t1 1 n3 2 n4 A 10 NULL NULL YES BTREE t1 1 n3 3 n1 A 10 NULL NULL BTREE t1 1 n3 4 n2 A 10 NULL NULL YES BTREE t1 1 n4 1 n4 A 10 NULL NULL YES BTREE t1 1 n4 2 n1 A 10 NULL NULL BTREE t1 1 n4 3 n2 A 10 NULL NULL YES BTREE t1 1 n4 4 n3 A 10 NULL NULL YES BTREE drop table t1; create table t1 (i int unsigned not null auto_increment primary key); alter table t1 rename t2; alter table t2 rename t1, add c char(10) comment "no comment"; show columns from t1; Field Type Null Key Default Extra i int(10) unsigned NO PRI NULL auto_increment c char(10) YES NULL drop table t1; create table t1 (a int, b int); alter table t1 add unique (a,b), add key (b); show keys from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 0 a 2 b A NULL NULL NULL YES BTREE t1 1 b 1 b A 100 NULL NULL YES BTREE analyze table t1; Table Op Msg_type Msg_text test.t1 analyze status OK show keys from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A 3 NULL NULL YES BTREE t1 0 a 2 b A 300 NULL NULL YES BTREE t1 1 b 1 b A 100 NULL NULL YES BTREE drop table t1; CREATE TABLE t1 (i int(10), index(i) ) ENGINE=MyISAM; ALTER TABLE t1 DISABLE KEYS; INSERT DELAYED INTO t1 VALUES(1),(2),(3); ALTER TABLE t1 ENABLE KEYS; drop table t1; CREATE TABLE t1 ( Host varchar(16) binary NOT NULL default '', User varchar(16) binary NOT NULL default '', PRIMARY KEY (Host,User) ) ENGINE=MyISAM; ALTER TABLE t1 DISABLE KEYS; LOCK TABLES t1 WRITE; INSERT INTO t1 VALUES ('localhost','root'),('localhost',''),('games','monty'); SHOW INDEX FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 PRIMARY 1 Host A NULL NULL NULL BTREE t1 0 PRIMARY 2 User A 0 NULL NULL BTREE ALTER TABLE t1 ENABLE KEYS; UNLOCK TABLES; CHECK TABLES t1; Table Op Msg_type Msg_text test.t1 check status OK DROP TABLE t1; CREATE TABLE t1 ( Host varchar(16) binary NOT NULL default '', User varchar(16) binary NOT NULL default '', PRIMARY KEY (Host,User), KEY (Host) ) ENGINE=MyISAM; ALTER TABLE t1 DISABLE KEYS; SHOW INDEX FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 PRIMARY 1 Host A NULL NULL NULL BTREE t1 0 PRIMARY 2 User A 0 NULL NULL BTREE t1 1 Host 1 Host A NULL NULL NULL BTREE disabled LOCK TABLES t1 WRITE; INSERT INTO t1 VALUES ('localhost','root'),('localhost',''); SHOW INDEX FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 PRIMARY 1 Host A NULL NULL NULL BTREE t1 0 PRIMARY 2 User A 0 NULL NULL BTREE t1 1 Host 1 Host A NULL NULL NULL BTREE disabled ALTER TABLE t1 ENABLE KEYS; SHOW INDEX FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 PRIMARY 1 Host A NULL NULL NULL BTREE t1 0 PRIMARY 2 User A 2 NULL NULL BTREE t1 1 Host 1 Host A 1 NULL NULL BTREE UNLOCK TABLES; CHECK TABLES t1; Table Op Msg_type Msg_text test.t1 check status OK LOCK TABLES t1 WRITE; ALTER TABLE t1 RENAME t2; UNLOCK TABLES; select * from t2; Host User localhost localhost root DROP TABLE t2; CREATE TABLE t1 ( Host varchar(16) binary NOT NULL default '', User varchar(16) binary NOT NULL default '', PRIMARY KEY (Host,User), KEY (Host) ) ENGINE=MyISAM; LOCK TABLES t1 WRITE; ALTER TABLE t1 DISABLE KEYS; SHOW INDEX FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 PRIMARY 1 Host A NULL NULL NULL BTREE t1 0 PRIMARY 2 User A 0 NULL NULL BTREE t1 1 Host 1 Host A NULL NULL NULL BTREE disabled DROP TABLE t1; create table t1 (a int); alter table t1 rename to ``; ERROR 42000: Incorrect table name '' rename table t1 to ``; ERROR 42000: Incorrect table name '' drop table t1; drop table if exists t1, t2; Warnings: Note 1051 Unknown table 't1' Note 1051 Unknown table 't2' create table t1 ( a varchar(10) not null primary key ) engine=myisam; create table t2 ( a varchar(10) not null primary key ) engine=merge union=(t1); flush tables; alter table t1 modify a varchar(10); show create table t2; Table Create Table t2 CREATE TABLE `t2` ( `a` varchar(10) NOT NULL, PRIMARY KEY (`a`) ) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`) flush tables; alter table t1 modify a varchar(10) not null; show create table t2; Table Create Table t2 CREATE TABLE `t2` ( `a` varchar(10) NOT NULL, PRIMARY KEY (`a`) ) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`) drop table if exists t1, t2; create table t1 (a int, b int, c int, d int, e int, f int, g int, h int,i int, primary key (a,b,c,d,e,f,g,i,h)) engine=MyISAM; insert into t1 (a) values(1); show table status like 't1'; Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t1 MyISAM 10 Fixed 1 37 X X X X X X X X latin1_swedish_ci NULL alter table t1 modify a int; show table status like 't1'; Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t1 MyISAM 10 Fixed 1 37 X X X X X X X X latin1_swedish_ci NULL drop table t1; create table t1 (a int not null, b int not null, c int not null, d int not null, e int not null, f int not null, g int not null, h int not null,i int not null, primary key (a,b,c,d,e,f,g,i,h)) engine=MyISAM; insert into t1 (a) values(1); Warnings: Warning 1364 Field 'b' doesn't have a default value Warning 1364 Field 'c' doesn't have a default value Warning 1364 Field 'd' doesn't have a default value Warning 1364 Field 'e' doesn't have a default value Warning 1364 Field 'f' doesn't have a default value Warning 1364 Field 'g' doesn't have a default value Warning 1364 Field 'h' doesn't have a default value Warning 1364 Field 'i' doesn't have a default value show table status like 't1'; Name Engine Version Row_format Rows Avg_row_length Data_length Max_data_length Index_length Data_free Auto_increment Create_time Update_time Check_time Collation Checksum Create_options Comment t1 MyISAM 10 Fixed 1 37 X X X X X X X X latin1_swedish_ci NULL drop table t1; set names koi8r; create table t1 (a char(10) character set koi8r); insert into t1 values ('ΤΕΣΤ'); select a,hex(a) from t1; a hex(a) ΤΕΣΤ D4C5D3D4 alter table t1 change a a char(10) character set cp1251; select a,hex(a) from t1; a hex(a) ΤΕΣΤ F2E5F1F2 alter table t1 change a a binary(4); select a,hex(a) from t1; a hex(a) ςερς F2E5F1F2 alter table t1 change a a char(10) character set cp1251; select a,hex(a) from t1; a hex(a) ΤΕΣΤ F2E5F1F2 alter table t1 change a a char(10) character set koi8r; select a,hex(a) from t1; a hex(a) ΤΕΣΤ D4C5D3D4 alter table t1 change a a varchar(10) character set cp1251; select a,hex(a) from t1; a hex(a) ΤΕΣΤ F2E5F1F2 alter table t1 change a a char(10) character set koi8r; select a,hex(a) from t1; a hex(a) ΤΕΣΤ D4C5D3D4 alter table t1 change a a text character set cp1251; select a,hex(a) from t1; a hex(a) ΤΕΣΤ F2E5F1F2 alter table t1 change a a char(10) character set koi8r; select a,hex(a) from t1; a hex(a) ΤΕΣΤ D4C5D3D4 delete from t1; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` char(10) CHARACTER SET koi8r DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 alter table t1 DEFAULT CHARACTER SET latin1; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` char(10) CHARACTER SET koi8r DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 alter table t1 CONVERT TO CHARACTER SET latin1; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` char(10) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 alter table t1 DEFAULT CHARACTER SET cp1251; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` char(10) CHARACTER SET latin1 DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=cp1251 drop table t1; create table t1 (myblob longblob,mytext longtext) default charset latin1 collate latin1_general_cs; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `myblob` longblob, `mytext` longtext COLLATE latin1_general_cs ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_general_cs alter table t1 character set latin2; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `myblob` longblob, `mytext` longtext CHARACTER SET latin1 COLLATE latin1_general_cs ) ENGINE=MyISAM DEFAULT CHARSET=latin2 drop table t1; CREATE TABLE t1 (a int PRIMARY KEY, b INT UNIQUE); ALTER TABLE t1 DROP PRIMARY KEY; SHOW CREATE TABLE t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) NOT NULL, `b` int(11) DEFAULT NULL, UNIQUE KEY `b` (`b`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ALTER TABLE t1 DROP PRIMARY KEY; ERROR 42000: Can't DROP 'PRIMARY'; check that column/key exists DROP TABLE t1; create table t1 (a int, b int, key(a)); insert into t1 values (1,1), (2,2); alter table t1 drop key no_such_key; ERROR 42000: Can't DROP 'no_such_key'; check that column/key exists alter table t1 drop key a; drop table t1; CREATE TABLE T12207(a int) ENGINE=MYISAM; ALTER TABLE T12207 DISCARD TABLESPACE; ERROR HY000: Table storage engine for 'T12207' doesn't have this option DROP TABLE T12207; create table t1 (a text) character set koi8r; insert into t1 values (_koi8r'ΤΕΣΤ'); select hex(a) from t1; hex(a) D4C5D3D4 alter table t1 convert to character set cp1251; select hex(a) from t1; hex(a) F2E5F1F2 drop table t1; create table t1 ( a timestamp ); alter table t1 add unique ( a(1) ); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys drop table t1; drop table if exists t1; create table t1 (a int, key(a)); show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE "this used not to disable the index" alter table t1 modify a int, disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE disabled alter table t1 enable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE alter table t1 modify a bigint, disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE disabled alter table t1 enable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE alter table t1 add b char(10), disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE disabled alter table t1 add c decimal(10,2), enable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE "this however did" alter table t1 disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE disabled desc t1; Field Type Null Key Default Extra a bigint(20) YES MUL NULL b char(10) YES NULL c decimal(10,2) YES NULL alter table t1 add d decimal(15,5); "The key should still be disabled" show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 a 1 a A NULL NULL NULL YES BTREE disabled drop table t1; "Now will test with one unique index" create table t1(a int, b char(10), unique(a)); show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE alter table t1 disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE alter table t1 enable keys; "If no copy on noop change, this won't touch the data file" "Unique index, no change" alter table t1 modify a int, disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE "Change the type implying data copy" "Unique index, no change" alter table t1 modify a bigint, disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE alter table t1 modify a bigint; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE alter table t1 modify a int; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE drop table t1; "Now will test with one unique and one non-unique index" create table t1(a int, b char(10), unique(a), key(b)); show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE alter table t1 disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE disabled alter table t1 enable keys; "If no copy on noop change, this won't touch the data file" "The non-unique index will be disabled" alter table t1 modify a int, disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE disabled alter table t1 enable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE "Change the type implying data copy" "The non-unique index will be disabled" alter table t1 modify a bigint, disable keys; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE disabled "Change again the type, but leave the indexes as_is" alter table t1 modify a int; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE disabled "Try the same. When data is no copied on similar tables, this is noop" alter table t1 modify a int; show indexes from t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 0 a 1 a A NULL NULL NULL YES BTREE t1 1 b 1 b A NULL NULL NULL YES BTREE disabled drop table t1; create database mysqltest; create table t1 (c1 int); alter table t1 rename mysqltest.t1; drop table t1; ERROR 42S02: Unknown table 't1' alter table mysqltest.t1 rename t1; drop table t1; create table t1 (c1 int); use mysqltest; drop database mysqltest; alter table test.t1 rename t1; ERROR 3D000: No database selected alter table test.t1 rename test.t1; use test; drop table t1; CREATE TABLE t1(a INT) ROW_FORMAT=FIXED; CREATE INDEX i1 ON t1(a); SHOW CREATE TABLE t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) DEFAULT NULL, KEY `i1` (`a`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ROW_FORMAT=FIXED DROP INDEX i1 ON t1; SHOW CREATE TABLE t1; Table Create Table t1 CREATE TABLE `t1` ( `a` int(11) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ROW_FORMAT=FIXED DROP TABLE t1; DROP TABLE IF EXISTS bug24219; DROP TABLE IF EXISTS bug24219_2; CREATE TABLE bug24219 (a INT, INDEX(a)); SHOW INDEX FROM bug24219; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment bug24219 1 a 1 a A NULL NULL NULL YES BTREE ALTER TABLE bug24219 RENAME TO bug24219_2, DISABLE KEYS; SHOW INDEX FROM bug24219_2; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment bug24219_2 1 a 1 a A NULL NULL NULL YES BTREE disabled DROP TABLE bug24219_2; drop table if exists table_24562; create table table_24562( section int, subsection int, title varchar(50)); insert into table_24562 values (1, 0, "Introduction"), (1, 1, "Authors"), (1, 2, "Acknowledgements"), (2, 0, "Basics"), (2, 1, "Syntax"), (2, 2, "Client"), (2, 3, "Server"), (3, 0, "Intermediate"), (3, 1, "Complex queries"), (3, 2, "Stored Procedures"), (3, 3, "Stored Functions"), (4, 0, "Advanced"), (4, 1, "Replication"), (4, 2, "Load balancing"), (4, 3, "High availability"), (5, 0, "Conclusion"); select * from table_24562; section subsection title 1 0 Introduction 1 1 Authors 1 2 Acknowledgements 2 0 Basics 2 1 Syntax 2 2 Client 2 3 Server 3 0 Intermediate 3 1 Complex queries 3 2 Stored Procedures 3 3 Stored Functions 4 0 Advanced 4 1 Replication 4 2 Load balancing 4 3 High availability 5 0 Conclusion alter table table_24562 add column reviewer varchar(20), order by title; select * from table_24562; section subsection title reviewer 1 2 Acknowledgements NULL 4 0 Advanced NULL 1 1 Authors NULL 2 0 Basics NULL 2 2 Client NULL 3 1 Complex queries NULL 5 0 Conclusion NULL 4 3 High availability NULL 3 0 Intermediate NULL 1 0 Introduction NULL 4 2 Load balancing NULL 4 1 Replication NULL 2 3 Server NULL 3 3 Stored Functions NULL 3 2 Stored Procedures NULL 2 1 Syntax NULL update table_24562 set reviewer="Me" where section=2; update table_24562 set reviewer="You" where section=3; alter table table_24562 order by section ASC, subsection DESC; select * from table_24562; section subsection title reviewer 1 2 Acknowledgements NULL 1 1 Authors NULL 1 0 Introduction NULL 2 3 Server Me 2 2 Client Me 2 1 Syntax Me 2 0 Basics Me 3 3 Stored Functions You 3 2 Stored Procedures You 3 1 Complex queries You 3 0 Intermediate You 4 3 High availability NULL 4 2 Load balancing NULL 4 1 Replication NULL 4 0 Advanced NULL 5 0 Conclusion NULL alter table table_24562 order by table_24562.subsection ASC, table_24562.section DESC; select * from table_24562; section subsection title reviewer 5 0 Conclusion NULL 4 0 Advanced NULL 3 0 Intermediate You 2 0 Basics Me 1 0 Introduction NULL 4 1 Replication NULL 3 1 Complex queries You 2 1 Syntax Me 1 1 Authors NULL 4 2 Load balancing NULL 3 2 Stored Procedures You 2 2 Client Me 1 2 Acknowledgements NULL 4 3 High availability NULL 3 3 Stored Functions You 2 3 Server Me alter table table_24562 order by 12; ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '12' at line 1 alter table table_24562 order by (section + 12); ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(section + 12)' at line 1 alter table table_24562 order by length(title); ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(title)' at line 1 alter table table_24562 order by (select 12 from dual); ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(select 12 from dual)' at line 1 alter table table_24562 order by no_such_col; ERROR 42S22: Unknown column 'no_such_col' in 'order clause' drop table table_24562; create table t1 (mycol int(10) not null); alter table t1 alter column mycol set default 0; desc t1; Field Type Null Key Default Extra mycol int(10) NO 0 drop table t1; create table t1(id int(8) primary key auto_increment) engine=heap; insert into t1 values (null); insert into t1 values (null); select * from t1; id 1 2 alter table t1 auto_increment = 50; alter table t1 engine = myisam; insert into t1 values (null); select * from t1; id 1 2 50 alter table t1 engine = heap; insert into t1 values (null); select * from t1; id 1 2 50 51 drop table t1; set @orig_sql_mode = @@sql_mode; set sql_mode="no_zero_date"; create table t1(f1 int); alter table t1 add column f2 datetime not null, add column f21 date not null; insert into t1 values(1,'2000-01-01','2000-01-01'); alter table t1 add column f3 datetime not null; ERROR 22007: Incorrect datetime value: '0000-00-00 00:00:00' for column 'f3' at row 1 alter table t1 add column f3 date not null; ERROR 22007: Incorrect date value: '0000-00-00' for column 'f3' at row 1 alter table t1 add column f4 datetime not null default '2002-02-02', add column f41 date not null; ERROR 22007: Incorrect date value: '0000-00-00' for column 'f41' at row 1 alter table t1 add column f4 datetime not null default '2002-02-02', add column f41 date not null default '2002-02-02'; select * from t1; f1 f2 f21 f4 f41 1 2000-01-01 00:00:00 2000-01-01 2002-02-02 00:00:00 2002-02-02 drop table t1; set sql_mode= @orig_sql_mode; create table t1 (v varchar(32)); insert into t1 values ('def'),('abc'),('hij'),('3r4f'); select * from t1; v def abc hij 3r4f alter table t1 change v v2 varchar(32); select * from t1; v2 def abc hij 3r4f alter table t1 change v2 v varchar(64); select * from t1; v def abc hij 3r4f update t1 set v = 'lmn' where v = 'hij'; select * from t1; v def abc lmn 3r4f alter table t1 add i int auto_increment not null primary key first; select * from t1; i v 1 def 2 abc 3 lmn 4 3r4f update t1 set i=5 where i=3; select * from t1; i v 1 def 2 abc 5 lmn 4 3r4f alter table t1 change i i bigint; select * from t1; i v 1 def 2 abc 5 lmn 4 3r4f alter table t1 add unique key (i, v); select * from t1 where i between 2 and 4 and v in ('def','3r4f','lmn'); i v 4 3r4f drop table t1; create table t1 (t varchar(255) default null, key t (t(80))) engine=myisam default charset=latin1; alter table t1 change t t text; drop table t1; CREATE TABLE t1 (a varchar(500)); ALTER TABLE t1 ADD b GEOMETRY NOT NULL, ADD SPATIAL INDEX(b); SHOW CREATE TABLE t1; Table Create Table t1 CREATE TABLE `t1` ( `a` varchar(500) DEFAULT NULL, `b` geometry NOT NULL, SPATIAL KEY `b` (`b`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ALTER TABLE t1 ADD KEY(b(50)); SHOW CREATE TABLE t1; Table Create Table t1 CREATE TABLE `t1` ( `a` varchar(500) DEFAULT NULL, `b` geometry NOT NULL, SPATIAL KEY `b` (`b`), KEY `b_2` (`b`(50)) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 ALTER TABLE t1 ADD c POINT; SHOW CREATE TABLE t1; Table Create Table t1 CREATE TABLE `t1` ( `a` varchar(500) DEFAULT NULL, `b` geometry NOT NULL, `c` point DEFAULT NULL, SPATIAL KEY `b` (`b`), KEY `b_2` (`b`(50)) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 CREATE TABLE t2 (a INT, KEY (a(20))); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys ALTER TABLE t1 ADD d INT; ALTER TABLE t1 ADD KEY (d(20)); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys ALTER TABLE t1 ADD e GEOMETRY NOT NULL, ADD SPATIAL KEY (e(30)); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys DROP TABLE t1; CREATE TABLE t1 (s CHAR(8) BINARY); INSERT INTO t1 VALUES ('test'); SELECT LENGTH(s) FROM t1; LENGTH(s) 4 ALTER TABLE t1 MODIFY s CHAR(10) BINARY; SELECT LENGTH(s) FROM t1; LENGTH(s) 4 DROP TABLE t1; CREATE TABLE t1 (s BINARY(8)); INSERT INTO t1 VALUES ('test'); SELECT LENGTH(s) FROM t1; LENGTH(s) 8 SELECT HEX(s) FROM t1; HEX(s) 7465737400000000 ALTER TABLE t1 MODIFY s BINARY(10); SELECT HEX(s) FROM t1; HEX(s) 74657374000000000000 SELECT LENGTH(s) FROM t1; LENGTH(s) 10 DROP TABLE t1; CREATE TABLE t1 (v VARCHAR(3), b INT); INSERT INTO t1 VALUES ('abc', 5); SELECT * FROM t1; v b abc 5 ALTER TABLE t1 MODIFY COLUMN v VARCHAR(4); SELECT * FROM t1; v b abc 5 DROP TABLE t1; create table t1 (a tinytext character set latin1); alter table t1 convert to character set utf8; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` text ) ENGINE=MyISAM DEFAULT CHARSET=utf8 drop table t1; create table t1 (a mediumtext character set latin1); alter table t1 convert to character set utf8; show create table t1; Table Create Table t1 CREATE TABLE `t1` ( `a` longtext ) ENGINE=MyISAM DEFAULT CHARSET=utf8 drop table t1; End of 5.0 tests drop table if exists t1, t2, t3; create table t1 (i int); create table t3 (j int); insert into t1 values (); insert into t3 values (); lock table t1 write, t3 read; alter table t1 modify i int default 1; insert into t1 values (); select * from t1; i NULL 1 alter table t1 change i c char(10) default "Two"; insert into t1 values (); select * from t1; c NULL 1 Two alter table t1 modify c char(10) default "Three", rename to t2; select * from t1; ERROR HY000: Table 't1' was not locked with LOCK TABLES select * from t2; ERROR HY000: Table 't2' was not locked with LOCK TABLES select * from t3; j NULL unlock tables; insert into t2 values (); select * from t2; c NULL 1 Two Three lock table t2 write, t3 read; alter table t2 change c vc varchar(100) default "Four", rename to t1; select * from t1; ERROR HY000: Table 't1' was not locked with LOCK TABLES select * from t2; ERROR HY000: Table 't2' was not locked with LOCK TABLES select * from t3; j NULL unlock tables; insert into t1 values (); select * from t1; vc NULL 1 Two Three Four drop tables t1, t3; DROP TABLE IF EXISTS `t+1`, `t+2`; CREATE TABLE `t+1` (c1 INT); ALTER TABLE `t+1` RENAME `t+2`; CREATE TABLE `t+1` (c1 INT); ALTER TABLE `t+1` RENAME `t+2`; ERROR 42S01: Table 't+2' already exists DROP TABLE `t+1`, `t+2`; CREATE TEMPORARY TABLE `tt+1` (c1 INT); ALTER TABLE `tt+1` RENAME `tt+2`; CREATE TEMPORARY TABLE `tt+1` (c1 INT); ALTER TABLE `tt+1` RENAME `tt+2`; ERROR 42S01: Table 'tt+2' already exists SHOW CREATE TABLE `tt+1`; Table Create Table tt+1 CREATE TEMPORARY TABLE `tt+1` ( `c1` int(11) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 SHOW CREATE TABLE `tt+2`; Table Create Table tt+2 CREATE TEMPORARY TABLE `tt+2` ( `c1` int(11) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 DROP TABLE `tt+1`, `tt+2`; CREATE TABLE `#sql1` (c1 INT); CREATE TABLE `@0023sql2` (c1 INT); SHOW TABLES; Tables_in_test #sql1 @0023sql2 RENAME TABLE `#sql1` TO `@0023sql1`; RENAME TABLE `@0023sql2` TO `#sql2`; SHOW TABLES; Tables_in_test #sql2 @0023sql1 ALTER TABLE `@0023sql1` RENAME `#sql-1`; ALTER TABLE `#sql2` RENAME `@0023sql-2`; SHOW TABLES; Tables_in_test #sql-1 @0023sql-2 INSERT INTO `#sql-1` VALUES (1); INSERT INTO `@0023sql-2` VALUES (2); DROP TABLE `#sql-1`, `@0023sql-2`; CREATE TEMPORARY TABLE `#sql1` (c1 INT); CREATE TEMPORARY TABLE `@0023sql2` (c1 INT); SHOW TABLES; Tables_in_test ALTER TABLE `#sql1` RENAME `@0023sql1`; ALTER TABLE `@0023sql2` RENAME `#sql2`; SHOW TABLES; Tables_in_test INSERT INTO `#sql2` VALUES (1); INSERT INTO `@0023sql1` VALUES (2); SHOW CREATE TABLE `#sql2`; Table Create Table #sql2 CREATE TEMPORARY TABLE `#sql2` ( `c1` int(11) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 SHOW CREATE TABLE `@0023sql1`; Table Create Table @0023sql1 CREATE TEMPORARY TABLE `@0023sql1` ( `c1` int(11) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 DROP TABLE `#sql2`, `@0023sql1`; DROP TABLE IF EXISTS t1; DROP TABLE IF EXISTS t2; CREATE TABLE t1 ( int_field INTEGER UNSIGNED NOT NULL, char_field CHAR(10), INDEX(`int_field`) ); DESCRIBE t1; Field Type Null Key Default Extra int_field int(10) unsigned NO MUL NULL char_field char(10) YES NULL SHOW INDEXES FROM t1; Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment t1 1 int_field 1 int_field A NULL NULL NULL BTREE INSERT INTO t1 VALUES (1, "edno"), (1, "edno"), (2, "dve"), (3, "tri"), (5, "pet"); "Non-copy data change - new frm, but old data and index files" ALTER TABLE t1 CHANGE int_field unsigned_int_field INTEGER UNSIGNED NOT NULL, RENAME t2; SELECT * FROM t1 ORDER BY int_field; ERROR 42S02: Table 'test.t1' doesn't exist SELECT * FROM t2 ORDER BY unsigned_int_field; unsigned_int_field char_field 1 edno 1 edno 2 dve 3 tri 5 pet DESCRIBE t2; Field Type Null Key Default Extra unsigned_int_field int(10) unsigned NO MUL NULL char_field char(10) YES NULL DESCRIBE t2; Field Type Null Key Default Extra unsigned_int_field int(10) unsigned NO MUL NULL char_field char(10) YES NULL ALTER TABLE t2 MODIFY unsigned_int_field BIGINT UNSIGNED NOT NULL; DESCRIBE t2; Field Type Null Key Default Extra unsigned_int_field bigint(20) unsigned NO MUL NULL char_field char(10) YES NULL DROP TABLE t2; CREATE TABLE t1 (f1 INT, f2 INT, f3 INT); INSERT INTO t1 VALUES (1, 2, NULL); SELECT * FROM t1; f1 f2 f3 1 2 NULL ALTER TABLE t1 MODIFY COLUMN f3 INT AFTER f1; SELECT * FROM t1; f1 f3 f2 1 NULL 2 ALTER TABLE t1 MODIFY COLUMN f3 INT AFTER f2; SELECT * FROM t1; f1 f2 f3 1 2 NULL DROP TABLE t1; create table t1 (c char(10) default "Two"); lock table t1 write; insert into t1 values (); alter table t1 modify c char(10) default "Three"; unlock tables; select * from t1; c Two check table t1; Table Op Msg_type Msg_text test.t1 check status OK drop table t1; DROP TABLE IF EXISTS t1; CREATE TABLE t1 (id int, c int) character set latin1; INSERT INTO t1 VALUES (1,1); ALTER TABLE t1 CHANGE c d int; affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 ALTER TABLE t1 CHANGE d c int; affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 ALTER TABLE t1 MODIFY c VARCHAR(10); affected rows: 1 info: Records: 1 Duplicates: 0 Warnings: 0 ALTER TABLE t1 CHANGE c d varchar(10); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 ALTER TABLE t1 CHANGE d c varchar(10); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 DROP TABLE t1; DROP TABLE IF EXISTS t1; CREATE TABLE t1 (id int, c int) character set utf8; INSERT INTO t1 VALUES (1,1); ALTER TABLE t1 CHANGE c d int; affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 ALTER TABLE t1 CHANGE d c int; affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 ALTER TABLE t1 MODIFY c VARCHAR(10); affected rows: 1 info: Records: 1 Duplicates: 0 Warnings: 0 ALTER TABLE t1 CHANGE c d varchar(10); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 ALTER TABLE t1 CHANGE d c varchar(10); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 DROP TABLE t1; create table t1(f1 int not null, f2 int not null, key (f1), key (f2)); select index_length into @unpaked_keys_size from information_schema.tables where table_name='t1'; alter table t1 pack_keys=1; select index_length into @paked_keys_size from information_schema.tables where table_name='t1'; select (@unpaked_keys_size > @paked_keys_size); (@unpaked_keys_size > @paked_keys_size) 1 select max_data_length into @orig_max_data_length from information_schema.tables where table_name='t1'; alter table t1 max_rows=100; select max_data_length into @changed_max_data_length from information_schema.tables where table_name='t1'; select (@orig_max_data_length > @changed_max_data_length); (@orig_max_data_length > @changed_max_data_length) 1 drop table t1; CREATE TABLE t1(a INT AUTO_INCREMENT PRIMARY KEY, b ENUM('a', 'b', 'c') NOT NULL); INSERT INTO t1 (b) VALUES ('a'), ('c'), ('b'), ('b'), ('a'); ALTER TABLE t1 MODIFY b ENUM('a', 'z', 'b', 'c') NOT NULL; SELECT * FROM t1; a b 1 a 2 c 3 b 4 b 5 a DROP TABLE t1; SET @save_sql_mode=@@sql_mode; SET sql_mode=strict_all_tables; CREATE TABLE t1 (a int NOT NULL default 42); INSERT INTO t1 values (); SELECT * FROM t1; a 42 ALTER TABLE t1 ALTER COLUMN a DROP DEFAULT; INSERT INTO t1 values (); ERROR HY000: Field 'a' doesn't have a default value INSERT INTO t1 (a) VALUES (11); SELECT * FROM t1 ORDER BY a; a 11 42 DROP TABLE t1; SET @@sql_mode=@save_sql_mode; # # Bug#45567: Fast ALTER TABLE broken for enum and set # DROP TABLE IF EXISTS t1; CREATE TABLE t1 (a ENUM('a1','a2')); INSERT INTO t1 VALUES ('a1'),('a2'); # No copy: No modification ALTER TABLE t1 MODIFY COLUMN a ENUM('a1','a2'); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 # No copy: Add new enumeration to the end ALTER TABLE t1 MODIFY COLUMN a ENUM('a1','a2','a3'); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 # Copy: Modify and add new to the end ALTER TABLE t1 MODIFY COLUMN a ENUM('a1','a2','xx','a5'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 # Copy: Remove from the end ALTER TABLE t1 MODIFY COLUMN a ENUM('a1','a2','xx'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 # Copy: Add new enumeration ALTER TABLE t1 MODIFY COLUMN a ENUM('a1','a2','a0','xx'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 # No copy: Add new enumerations to the end ALTER TABLE t1 MODIFY COLUMN a ENUM('a1','a2','a0','xx','a5','a6'); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 DROP TABLE t1; CREATE TABLE t1 (a SET('a1','a2')); INSERT INTO t1 VALUES ('a1'),('a2'); # No copy: No modification ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2'); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 # No copy: Add new to the end ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2','a3'); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 # Copy: Modify and add new to the end ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2','xx','a5'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 # Copy: Remove from the end ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2','xx'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 # Copy: Add new member ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2','a0','xx'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 # No copy: Add new to the end ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2','a0','xx','a5','a6'); affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 # Copy: Numerical incrase (pack lenght) ALTER TABLE t1 MODIFY COLUMN a SET('a1','a2','a0','xx','a5','a6','a7','a8','a9','a10'); affected rows: 2 info: Records: 2 Duplicates: 0 Warnings: 0 DROP TABLE t1; CREATE TABLE t1 (f1 TIMESTAMP NULL DEFAULT NULL, f2 INT(11) DEFAULT NULL) ENGINE=MYISAM DEFAULT CHARSET=utf8; INSERT INTO t1 VALUES (NULL, NULL), ("2009-10-09 11:46:19", 2); this should affect no rows as there is no real change ALTER TABLE t1 CHANGE COLUMN f1 f1_no_real_change TIMESTAMP NULL DEFAULT NULL; affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 DROP TABLE t1; # # Bug #31145: ALTER TABLE DROP COLUMN, ADD COLUMN crashes (linux) # or freezes (win) the server # CREATE TABLE t1 (a TEXT, id INT, b INT); ALTER TABLE t1 DROP COLUMN a, ADD COLUMN c TEXT FIRST; DROP TABLE t1; End of 5.1 tests CREATE TABLE t1(c CHAR(10), i INT UNSIGNED AUTO_INCREMENT NOT NULL PRIMARY KEY); INSERT INTO t1 VALUES('a',2),('b',4),('c',6); ALTER TABLE t1 DROP i, ADD i INT UNSIGNED NOT NULL AUTO_INCREMENT, AUTO_INCREMENT = 1; DROP TABLE t1; CREATE TABLE t1 (a CHAR(1), PRIMARY KEY (a(255))); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys CREATE TABLE t1 (a CHAR(1)); ALTER TABLE t1 ADD PRIMARY KEY (a(20)); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys ALTER TABLE t1 ADD KEY (a(20)); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys CREATE UNIQUE INDEX i1 ON t1 (a(20)); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys CREATE INDEX i2 ON t1 (a(20)); ERROR HY000: Incorrect prefix key; the used key part isn't a string, the used length is longer than the key part, or the storage engine doesn't support unique prefix keys DROP TABLE t1; CREATE TABLE t1 (id int); INSERT INTO t1 VALUES (1), (2); ALTER TABLE t1 ADD COLUMN (f1 INT), ADD COLUMN (f2 INT), ADD KEY f2k(f2); DROP TABLE t1; # # Test for bug #53820 "ALTER a MEDIUMINT column table causes full # table copy". # DROP TABLE IF EXISTS t1; CREATE TABLE t1 (a INT, b MEDIUMINT); INSERT INTO t1 VALUES (1, 1), (2, 2); # The below ALTER should not copy table and so no rows should # be shown as affected. ALTER TABLE t1 CHANGE a id INT; affected rows: 0 info: Records: 0 Duplicates: 0 Warnings: 0 DROP TABLE t1; # # Bug#11754461 CANNOT ALTER TABLE WHEN KEY PREFIX TOO LONG # DROP DATABASE IF EXISTS db1; CREATE DATABASE db1 CHARACTER SET utf8; CREATE TABLE db1.t1 (bar TINYTEXT, KEY (bar(100))); ALTER TABLE db1.t1 ADD baz INT; DROP DATABASE db1; # # Bug#11938039 RE-EXECUTION OF FRM-ONLY ALTER TABLE WITH RENAME # CLAUSE FAILS OR ABORTS SERVER. # drop table if exists t1; create table t1 (a int); prepare stmt1 from 'alter table t1 alter column a set default 1, rename to t2'; execute stmt1; rename table t2 to t1; # The below statement should succeed and not emit error or abort server. execute stmt1; deallocate prepare stmt1; drop table t2;