Question

以下查询是一个更大的复杂查询的原型问题是我应该能够根据用户输入以任何顺序（即ASC和DESC）对任何列进行排序。

CREATE table #Table1(
Name varchar(10) PRIMARY key,
DOB DateTime,
Rate numeric(10,2)  
)

INSERT INTO #Table1 (Name,DOB,Rate) values ('Name1','2/2/2012',10.23)
INSERT INTO #Table1 (Name,DOB,Rate) values ('Name2','3/2/2012',120.23)
INSERT INTO #Table1 (Name,DOB,Rate) values ('Name3','4/2/2012',110.23)
INSERT INTO #Table1 (Name,DOB,Rate) values ('Name4','5/2/2012',140.23)
INSERT INTO #Table1 (Name,DOB,Rate) values ('Name15','6/2/2012',130.23)
INSERT INTO #Table1 (Name,DOB,Rate) values ('Name6','2/21/2012',1120.23)

Declare @SortColumn varchar(10)
DECLARE @SortExpression varchar (10)

SET @SortColumn = 'DOB'
SET @SortExpression = 'DESC' -- Need to sort in both ASC and DESC

Select 
            Name,
            DOB,
            Rate,
            ROW_NUMBER() OVER 
                (ORDER BY 
                    CASE WHEN @SortColumn = 'Name' then Name
                         WHEN @SortColumn = 'DOB' THEN DOB
                         WHEN @SortColumn = 'Rate' THEN Rate
                    END  +  @SortExpression 
                ) AS RowNumber  
                FROM 
                #Table1

Answer 1

您似乎需要CAST()和CONVERT() CASE中的项目才能让它发挥作用：

Declare @SortColumn varchar(10)
DECLARE @SortExpression varchar (10)

SET @SortColumn = 'DOB'
SET @SortExpression = 'DESC' -- Need to sort in both ASC and DESC

Select 
   Name,
   DOB,
   Rate,
   ROW_NUMBER() OVER 
   (ORDER BY 
       CASE WHEN @SortColumn = 'Name' then Name
            WHEN @SortColumn = 'DOB' THEN convert(char(10), DOB, 120)
            WHEN @SortColumn = 'Rate' THEN Cast(Rate as varchar(10))
       END  ASC
    ) AS RowNumberASC,
    ROW_NUMBER() OVER 
    (ORDER BY 
       CASE WHEN @SortColumn = 'Name' then Name
            WHEN @SortColumn = 'DOB' THEN convert(char(10), DOB, 120)
            WHEN @SortColumn = 'Rate' THEN Cast(Rate as varchar(10))
      END DESC
    ) AS RowNumberDESC
FROM Table1

请参阅SQL Fiddle with Demo

由于@Martin指出ASC，DESC无法参数化。

Answer 2

如果您需要动态切换ASC和DESC，则必须使用动态声明。
SQL小提琴here。请注意SQL Injection！

EXECUTE(' SELECT Name, DOB, Rate,'
      + ' ROW_NUMBER() OVER( ORDER BY ' + @SortColumn + ' ' + @SortExpression
      + ' ) AS RowNumber'
      + ' FROM Table1');

如果您的查询很复杂，请考虑将其放入视图中并从该视图中选择以允许对该部分进行编译时检查。

如何在ROW_NUMBER（）OVER（ORDER BY子句）中对datetime进行排序

2 个答案: