mysql alter example

alter table `user_movement_log` 
Add column GatewayId int not null default 0 AFTER `Regionid` (在哪个字段后面添加)

 alter table x_connection add `FEX-N752` varchar(10) default null;

//主键

alter table tabelname add new_field_id int(5) unsigned default 0 not null auto_increment ,add primary key (new_field_id);
//增加一个新列

alter table t2 add d timestamp; 

alter table infos add ex tinyint not null default '0';

//删除列

alter table t2 drop column c;
//重命名列

alter table t1 change a b integer;

//改变列的类型

alter table t1 change b b bigint not null; 

alter table infos change list list tinyint not null default '0';

//重命名表

alter table t1 rename t2;
加索引

mysql> alter table tablename change depno depno int(5) not null; 

mysql> alter table tablename add index 索引名 (字段名1[,字段名2 …]); 

mysql> alter table tablename add index emp_name (name);

加主关键字的索引

mysql> alter table tablename add primary key(id);
加唯一限制条件的索引

mysql> alter table tablename add unique emp_name2(cardnumber);
删除某个索引

mysql>alter table tablename drop index emp_name;
修改表:

增加字段:

mysql> ALTER TABLE table_name ADD field_name field_type;
修改原字段名称及类型:

mysql> ALTER TABLE table_name CHANGE old_field_name new_field_name field_type;

eg:alter table dip_mr_log change map_output_byte map_output_byte bigint unsigned DEFAULT '0';   

删除字段:

mysql> ALTER TABLE table_name DROP field_name;  

 

posted @ 2015-05-16 15:17  hao.ma  阅读(156)  评论(0编辑  收藏  举报