使用NOT IN实现MySQL条件GROUP BY以从重复的列值中过滤记录
让我们首先创建一个表-
mysql> create table DemoTable ( Name varchar(40), Score int );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable values('Adam',89);
mysql> insert into DemoTable values('Adam',89);
mysql> insert into DemoTable values('Chris',89);
mysql> insert into DemoTable values('Chris',89);
mysql> insert into DemoTable values('Bob',98);
mysql> insert into DemoTable values('Bob',89);使用select语句显示表中的所有记录-
mysql> select *from DemoTable;
这将产生以下输出-
+-------+-------+ | Name | Score | +-------+-------+ | Adam | 89 | | Adam | 89 | | Chris | 89 | | Chris | 89 | | Bob | 98 | | Bob | 89 | +-------+-------+ 6 rows in set (0.00 sec)
以下是使用NOT实现条件GROUPBY的查询IN()-
mysql> select distinct Name from DemoTable where Name not in(select Name from DemoTable where Score <> 89);
这将产生以下输出-
+-------+ | Name | +-------+ | Adam | | Chris | +-------+q 2 rows in set (0.06 sec)