MySQL 表的常见操作_MySQL
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MySQL 表的常见操作
查看列:desc 表名; 修改表名:alter table t_book rename to bbb; 添加列:alter table 表名 add column 列名 varchar(30); 删除列:alter table 表名 drop column 列名; 修改列名MySQL: alter table bbb change nnnnn hh int; 修改列名SQLServer:exec sp_rename't_student.name','nn','column'; 修改列名Oracle:lter table bbb rename column nnnnn to hh int; 修改列属性:alter table t_book modify name varchar(22); sp_rename:SQLServer 内置的存储过程,用与修改表的定义。MySQL 查看约束,添加约束,删除约束 添加列,修改列,删除列 查看表的字段信息:desc 表名; 查看表的所有信息:show create table 表名; 添加主键约束:alter table 表名 add constraint 主键 (形如:PK_表名) primary key 表名(主键字段); 添加外键约束:alter table 从表 add constraint 外键(形如:FK_从表_主表) foreign key 从表(外键字段) references 主表(主键字段); 删除主键约束:alter table 表名 drop primary key; 删除外键约束:alter table 表名 drop foreign key 外键(区分大小写); 修改表名:alter table t_book rename to bbb; 添加列:alter table 表名 add column 列名 varchar(30); 删除列:alter table 表名 drop column 列名; 修改列名MySQL: alter table bbb change nnnnn hh int; 修改列名SQLServer:exec sp_rename't_student.name','nn','column'; 修改列名Oracle:alter table bbb rename column nnnnn to hh int; 修改列属性:alter table t_book modify name varchar(22);sp_rename:SQLServer 内置的存储过程,用与修改表的定义。
参考:http://blog.csdn.net/ws84643557/article/details/6939846
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