A,SELECT * FROM [order details] ORDER BY productid,employeeid COMPUTE SUM (quantity)B, SELECT * FROM [order details] ORDER BY productid,employeeid COMPUTE SUM (quantity) BY productid
C,SELECT * FROM [order details] ORDER BY productid,employeeid COMPUTE SUM (quantity) BY employeeid
D,SELECT * FROM [order details] ORDER BY productid,employeeid COMPUTE SUM (quantity) BY employeeid,productid
答案选CD,实在不懂,CD选项好像也只是将分组类别改变而已,跪求大虾解释
C,SELECT * FROM [order details] ORDER BY productid,employeeid COMPUTE SUM (quantity) BY employeeid
D,SELECT * FROM [order details] ORDER BY productid,employeeid COMPUTE SUM (quantity) BY employeeid,productid
答案选CD,实在不懂,CD选项好像也只是将分组类别改变而已,跪求大虾解释
官方已经不推荐使用这个方式,建议改用ROLLUP
--运行正确
SELECT * FROM sys.objects
ORDER BY object_id,is_ms_shipped
COMPUTE SUM (schema_id)--运行正确
SELECT * FROM sys.objects
ORDER BY object_id,is_ms_shipped
COMPUTE SUM (parent_object_id) BY object_id
/*
消息 143,级别 15,状态 1,第 3 行
在排序依据列表中没有找到 COMPUTE BY 子句中的某一项。
计算依据列表中的所有表达式也必须同时出现在排序依据列表中。compute by中的列只能是object_id,或者就是object_id和is_ms_shipped
*/
SELECT * FROM sys.objects
ORDER BY object_id,is_ms_shipped
COMPUTE SUM (parent_object_id) BY is_ms_shipped
/*
消息 143,级别 15,状态 1,第 3 行
在排序依据列表中没有找到 COMPUTE BY 子句中的某一项。
计算依据列表中的所有表达式也必须同时出现在排序依据列表中。也就是order by中列和compute by中的列的顺序要一样才对,否则报错。
*/
SELECT * FROM sys.objects
ORDER BY object_id,is_ms_shipped
COMPUTE SUM (parent_object_id) BY is_ms_shipped ,object_id
--> 请问题目是什么? 答案AB的语法上也没有错误的,关键是题目问的是什么.