ORDER BY 子句的 CASE WHEN 语句

Question

我使用的是 SQL Server 2008 R2。

我想要对表中的记录进行基于优先级的排序。

因此我在 ORDER BY 子句中使用 CASE WHEN 语句。 ORDER BY 子句如下：

ORDER BY 
CASE WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount desc, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END, 
CASE WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount desc, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
Case WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount DESC, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
CASE WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount DESC, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
Case WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount DESC, TblList.LastName ASC, TblList.FirstName ASC, Patlist.MiddleName ASC END

但是它给出了

Incorrect syntax near the keyword 'desc'

有什么解决办法吗？

我还可以：

TblList.PinRequestCount <> 0 and TblList.HighCallAlertCount <> 0 and
TblList.HighAlertCount <> 0` and TblList.MediumCallAlertCount <> 0 and  
TblList.MediumAlertCount <> 0 

同时。

Answer 1

CASE

是一个表达式 - 它返回一个单个标量值（每行）。它无法返回其他内容的解析树的复杂部分，例如

ORDER BY

语句的

SELECT

子句。

看起来你只需要：

ORDER BY 
CASE WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount END desc,
CASE WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount END desc, 
Case WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount END DESC,
CASE WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount END DESC,
Case WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount END DESC,
TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC

或者可能：

ORDER BY 
CASE
   WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount
   WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount
   WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount
   WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount
   WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount
END desc,
TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC

分辨上面的哪一个（或其他内容）是您正在寻找的内容有点棘手，因为您 a) 没有 解释 您想要实现的实际排序顺序，并且 b) 没有提供任何样本数据和预期结果，我们可以尝试从中推断您想要实现的实际排序顺序。

---

这可能就是我们正在寻找的答案：

ORDER BY 
CASE
   WHEN TblList.PinRequestCount <> 0 THEN 5
   WHEN TblList.HighCallAlertCount <> 0 THEN 4
   WHEN TblList.HighAlertCount <> 0 THEN 3
   WHEN TblList.MediumCallAlertCount <> 0 THEN 2
   WHEN TblList.MediumAlertCount <> 0 THEN 1
END desc,
CASE
   WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount
   WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount
   WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount
   WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount
   WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount
END desc,
TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC

Answer 2

来自这里的另一个简单示例..

SELECT * FROM dbo.Employee
ORDER BY 
 CASE WHEN Gender='Male' THEN EmployeeName END Desc,
 CASE WHEN Gender='Female' THEN Country END ASC

Answer 3

也许你可以使用

WITH

子句 :

WITH request AS (
    SELECT id
         , CASE
               WHEN a > 100 THEN 1
               ELSE 0
        END AS example
    FROM table
)
SELECT *
FROM request
ORDER BY example DESC

它也适用于

WHERE

子句

Answer 4

也许你可以优先考虑： #例如，我们要显示大于 2000 的 Year_of 版本

选择名称、发布年份、其他销售额、全球销售额 来自游戏 订购依据 案件 当 Year_of_release >= 2000 那么 0 其他1 结束，

#当year_of_release >= 2000时按global_sales排序，否则按 其他_销售 案件 当year_of_release >= 2000 时，那么global_sales ELSE other_sales
结束说明，

#最后，如果 global_sales 与 other_sales 相等，则按 id 升序排序 id ASC；

Answer 5

declare @OrderByCmd  nvarchar(2000)
declare @OrderByName nvarchar(100)
declare @OrderByCity nvarchar(100)
set @OrderByName='Name'    
set @OrderByCity='city'
set @OrderByCmd= 'select * from customer Order By '+@OrderByName+','+@OrderByCity+''
EXECUTE sp_executesql @OrderByCmd