更新基于MySQL中StudentId值的表？
让我们首先创建一个表-
mysql> create table DemoTable633 (StudentId char(2) not null primary key,StudentName varchar(100));
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable633 values('10','Chris');
mysql> insert into DemoTable633 values('20','Sam');
mysql> insert into DemoTable633 values('30','David');使用select语句显示表中的所有记录-
mysql> select *from DemoTable633;
这将产生以下输出-
+-----------+-------------+ | StudentId | StudentName | +-----------+-------------+ | 10 | Chris | | 20 | Sam | | 30 | David | +-----------+-------------+ 3 rows in set (0.00 sec)
现在让我们使用UPDATE根据StudentID更新上表-
mysql> update DemoTable633 set StudentName='Bob' where StudentId='20'; Rows matched: 1 Changed: 1 Warnings: 0
让我们再次检查表记录-
mysql> select *from DemoTable633;
这将产生以下输出-
+-----------+-------------+ | StudentId | StudentName | +-----------+-------------+ | 10 | Chris | | 20 | Bob | | 30 | David | +-----------+-------------+ 3 rows in set (0.00 sec)