在MySQL中交换特定的列值

让我们首先创建一个表table-

create table DemoTable1504 -> ( -> Id int, -> FirstName varchar(20) -> );

使用插入命令在表中插入一些记录-

insert into DemoTable1504 values(101,Chris); insert into DemoTable1504 values(102,Bob); insert into DemoTable1504 values(103,David); insert into DemoTable1504 values(104,Mike);

使用select语句显示表中的所有记录-

select * from DemoTable1504 ;

这将产生以下输出-

+------+-----------+ | Id | FirstName | +------+-----------+ | 101 | Chris | | 102 | Bob | | 103 | David | | 104 | Mike | +------+-----------+ 4 rows in set (0.00 sec)

以下是交换特定列值的查询-

update DemoTable1504 -> set FirstName=Carol -> where Id=103 -> and FirstName <> Carol; Rows matched: 1 Changed: 1 Warnings: 0

让我们再次检查表记录-

select * from DemoTable1504;

这将产生以下输出-

+------+-----------+ | Id | FirstName | +------+-----------+ | 101 | Chris | | 102 | Bob | | 103 | Carol | | 104 | Mike | +------+-----------+ 4 rows in set (0.00 sec)