sql - sql中where子句条件中的case语句

Question

我有一个这样的存储过程：

ALTER PROCEDURE [dbo].[hr_SearchVacanciesAdmin]
    @SearchText NVARCHAR(50) = NULL,
    @CompanyName NVARCHAR(100) = NULL,
    @DutyStationID INT = NULL,
    @VacancyCategoryIDs VARCHAR(1000) = NULL,
    @Status INT,
    @Language INT = 1

BEGIN

SELECT * from table
where 
  deleted = 0
  and status = @status
  and catname  = &searchtext

..
..
..
END

我想在 where 条件中添加 case 语句，以便如果 @status = 4 则不检查 delete =。我尝试关注但不工作

WHERE 
  1 = CASE 
        WHEN @Status = 4 
        THEN @status

        WHEN dbo.hr_Vacancies.Deleted = 0 
             --Search Criteria
             AND dbo.hr_Vacancies.Status = @Status 
        THEN @Status
      END

Answer 1

您不需要 CASE 语句来实现此功能。以下会很好：

SELECT * 
from   table
where  (deleted = 0 OR @status=4)
and    status = @status
and    catname = @searchtext

另请注意，您的代码&searchtext在where子句中引用，但这应该@searchtext按照这个答案（即前缀@not &）。

Answer 2

@RB 是正确的，您不需要案例，但您可以使用带有此技巧的案例，这在其他情况下也很有用：

 Where deleted = case @status when 4 then deleted else 0 end 

Answer 3

您可以使用此构造作为SELECT查询的开头：

Select * from table
WHERE
((1 = CASE WHEN @Status = 4 THEN 1 ELSE 0 END)
OR
dbo.hr_Vacancies.Deleted = 0)
AND
dbo.hr_Vacancies.Status = @Status