MySQL在WHERE子句中实现OR运算符?
当任一操作数为true时,OR运算符将给出true结果。现在让我们看一个示例并创建一个表-
mysql> create table DemoTable663(ClientId int,ClientName varchar(100),ClientAge int);
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable663 values(100,'Chris',45); mysql> insert into DemoTable663 values(101,'Robert',29); mysql> insert into DemoTable663 values(102,'John',45); mysql> insert into DemoTable663 values(103,'Chris',35); mysql> insert into DemoTable663 values(104,'Sam',45);
使用select语句显示表中的所有记录-
mysql> select *from DemoTable663;
这将产生以下输出-
+----------+------------+-----------+ | ClientId | ClientName | ClientAge | +----------+------------+-----------+ | 100 | Chris | 45 | | 101 | Robert | 29 | | 102 | John | 45 | | 103 | Chris | 35 | | 104 | Sam | 45 | +----------+------------+-----------+ 5 rows in set (0.00 sec)
以下是实现OR运算符的查询-
mysql> select *from DemoTable663 where ClientName='Chris' OR ClientAge=45;
这将产生以下输出-
+----------+------------+-----------+ | ClientId | ClientName | ClientAge | +----------+------------+-----------+ | 100 | Chris | 45 | | 102 | John | 45 | | 103 | Chris | 35 | | 104 | Sam | 45 | +----------+------------+-----------+ 4 rows in set (0.00 sec)