在 MySQL 中仅更新单个列值
mysqlmysqli database
首先我们创建一个表 −
mysql> create table DemoTable1605 -> ( -> StudentId int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> StudentName varchar(20), -> StudentCountryName varchar(20) -> ); Query OK, 0 rows affected (0.48 sec)
使用 insert 命令在表中插入一些记录 −
mysql> insert into DemoTable1605(StudentName,StudentCountryName) values('Adam','AUS');
Query OK, 1 row affected (0.21 sec)
mysql> insert into DemoTable1605(StudentName,StudentCountryName) values('John','US');
Query OK, 1 row affected (0.08 sec)
mysql> insert into DemoTable1605(StudentName,StudentCountryName) values('Bob','UK');
Query OK, 1 row affected (0.11 sec)
使用 select 语句显示表中的所有记录 −
mysql> select * from DemoTable1605;
这将产生以下输出 −
+-----------+-------------+--------------------+ | StudentId | StudentName | StudentCountryName | +-----------+-------------+--------------------+ | 1 | Adam | AUS | | 2 | John | US | | 3 | Bob | UK | +-----------+-------------+--------------------+ 3 rows in set (0.00 sec)
以下是在 MySQL 中仅更新单个列值的查询 −
mysql> update DemoTable1605 set StudentName='Chris' where StudentCountryName='UK'; Query OK, 1 row affected (0.09 sec) Rows matched: 1 Changed: 1 Warnings: 0
让我们再次检查表记录 −
mysql> select * from DemoTable1605;
这将产生以下输出 −
+-----------+-------------+--------------------+ | StudentId | StudentName | StudentCountryName | +-----------+-------------+--------------------+ | 1 | Adam | AUS | | 2 | John | US | | 3 | Chris | UK | +-----------+-------------+--------------------+ 3 rows in set (0.00 sec)
