取决于参数值的可选 where 子句

Question

我希望此查询的 where 语句是可选的，具体取决于参数 @RetrieveAll 的值。如果@RetrieveAll 为false/null，则使用where 语句，如果为true，则应忽略它。

    @IncludeErrors bit = 1,
    @IncludeAccess bit = 1,
    @IncludeLogins bit = 1,
    @RetrieveAll bit = NULL
SELECT
 //...
FROM
(

) AS a
WHERE
a.RowNumber BETWEEN @ItemCountStart AND @ItemCountEnd

有没有办法做到这一点？

Answer 1

SELECT
 //...
FROM
(

) AS a
WHERE
(a.RowNumber BETWEEN @ItemCountStart AND @ItemCountEnd AND @RetrieveAll IS NULL)
OR
@RetrieveAll IS NOT NULL

Answer 2

你应该试试这个，

Select * from Tablename a
Where 
1 = case when isnull(@RetriveAll,0) == 0 then 
        case when a.RowNumber BETWEEN @ItemCountStart AND @ItemCountEnd then 1 else 0 end
    else 1 end