程式媛計劃——mysql修改表結構

標籤：cte   table   mys   查看   修改欄位   code   資料   0.00   change   

#查看錶的結構

mysql> desc score;+------------+--------------+------+-----+---------+----------------+| Field      | Type         | Null | Key | Default | Extra          |+------------+--------------+------+-----+---------+----------------+| id         | int(4)       | NO   | PRI | NULL    | auto_increment || name       | char(20)     | NO   |     | NULL    |                || score      | double(16,2) | YES  |     | NULL    |                || evaluation | char(20)     | YES  |     | normal  |                |+------------+--------------+------+-----+---------+----------------+4 rows in set (0.00 sec)

 

 

#alter對欄位操作

#添加欄位

mysql> alter table exam_score add other int(4) default 10;Query OK, 0 rows affected (0.05 sec)Records: 0  Duplicates: 0  Warnings: 0

#修改欄位變為另一個欄位

mysql> alter table exam_score change other evaluation char(20) default ‘normal‘; Query OK, 4 rows affected (0.02 sec)Records: 4  Duplicates: 0  Warnings: 0

#刪除欄位(即刪除欄位中的所有資料)

mysql> alter table exam_score drop column other;Query OK, 0 rows affected (0.05 sec)Records: 0  Duplicates: 0  Warnings: 0

 

#修改表名

mysql> rename table exam_score to score;Query OK, 0 rows affected (0.01 sec)

 

程式媛計劃——mysql修改表結構