仅更新MySQL字段中的int
让我们首先创建一个表-
mysql> create table DemoTable702 ( StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, StudentName varchar(100), StudentScore int );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable702(StudentName,StudentScore) values('Chris',56);
mysql> insert into DemoTable702(StudentName,StudentScore) values('Robert',21);
mysql> insert into DemoTable702(StudentName,StudentScore) values('Mike',89);
mysql> insert into DemoTable702(StudentName,StudentScore) values('David',99);使用select语句显示表中的所有记录-
mysql> select *from DemoTable702;
这将产生以下输出-
+-----------+-------------+--------------+ | StudentId | StudentName | StudentScore | +-----------+-------------+--------------+ | 1 | Chris | 56 | | 2 | Robert | 21 | | 3 | Mike | 89 | | 4 | David | 99 | +-----------+-------------+--------------+ 4 rows in set (0.00 sec)
这是在MySQL中更新int的查询-
mysql> update DemoTable702 set StudentScore=StudentScore+9 where StudentId=2; Rows matched: 1 Changed: 1 Warnings: 0
让我们再次检查表记录-
mysql> select *from DemoTable702;
这将产生以下输出-
+-----------+-------------+--------------+ | StudentId | StudentName | StudentScore | +-----------+-------------+--------------+ | 1 | Chris | 56 | | 2 | Robert | 30 | | 3 | Mike | 89 | | 4 | David | 99 | +-----------+-------------+--------------+ 4 rows in set (0.00 sec)