维护在MySQL中传递的ID的自定义顺序
要维持ID的自定义顺序，请使用ORDERBYCASE语句。让我们首先创建一个表-
mysql> create table DemoTable1550 -> ( -> Id int, -> Name varchar(20) -> );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable1550 values(101,'Chris'); mysql> insert into DemoTable1550 values(110,'Bob'); mysql> insert into DemoTable1550 values(105,'Carol'); mysql> insert into DemoTable1550 values(109,'Mike');
使用select语句显示表中的所有记录-
mysql> select * from DemoTable1550;
这将产生以下输出-
+------+-------+ | Id | Name | +------+-------+ | 101 | Chris | | 110 | Bob | | 105 | Carol | | 109 | Mike | +------+-------+ 4 rows in set (0.00 sec)
这是维护传递的ID顺序的查询-
mysql> select * from DemoTable1550 -> where Id IN(109,101,110) -> order by case Id -> when 109 then 1001 -> when 101 then 1002 -> when 110 then 1003 -> end;
这将产生以下输出-
+------+-------+ | Id | Name | +------+-------+ | 109 | Mike | | 101 | Chris | | 110 | Bob | +------+-------+ 3 rows in set (0.00 sec)