用类似的例子在MySQL中实现WHERE IN vs OR
IN在MySQL中使用索引，而OR在MySQL中不使用索引。
让我们首先创建一个表-
mysql> create table DemoTable711 ( Id int, Name varchar(100) );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable711 values(100,'Chris'); mysql> insert into DemoTable711 values(101,'Robert'); mysql> insert into DemoTable711 values(102,'Carol'); mysql> insert into DemoTable711 values(103,'Mike'); mysql> insert into DemoTable711 values(104,'Sam');
使用select语句显示表中的所有记录-
mysql> select *from DemoTable711;
这将产生以下输出-
+------+--------+ | Id | Name | +------+--------+ | 100 | Chris | | 101 | Robert | | 102 | Carol | | 103 | Mike | | 104 | Sam | +------+--------+ 5 rows in set (0.00 sec)
以下是对IN()方法的查询-
mysql> select *from DemoTable711 where Id IN(101,103,104);
这将产生以下输出-
+------+--------+ | Id | Name | +------+--------+ | 101 | Robert | | 103 | Mike | | 104 | Sam | +------+--------+ 3 rows in set (0.03 sec)
以下是对OR的查询-
mysql> select *from DemoTable711 where Id=101 OR Id=103 OR Id=104;
这将产生以下输出-
+------+--------+ | Id | Name | +------+--------+ | 101 | Robert | | 103 | Mike | | 104 | Sam | +------+--------+ 3 rows in set (0.00 sec)