Question

以下是我的发言：

SELECT  
    CASE 
        WHEN @UserRole = 1 THEN 1
        ELSE 0
    END AS [CanEdit],
        F.FundingStreamName       
FROM    FundingStream AS F
        LEFT JOIN Projects AS P ON P.FundingStream = F.FundingStreamID 
WHERE   ProjectNumber = @ProjectNumber

我注意到如果FundingStreamID为空，case语句也不会返回任何内容，无论是否有资金流，我如何才能执行case语句？感谢。

Answer 1

我认为问题在于你的where条款是＆＃34;撤消＆＃34;你的左外连接。尝试将条件移至on子句：

SELECT (CASE WHEN @UserRole = 1 THEN 1
             ELSE 0
        END) AS [CanEdit],
       F.FundingStreamName       
FROM FundingStream F LEFT JOIN
     Projects P
     ON P.FundingStream = F.FundingStreamID AND
        P.ProjectNumber = @ProjectNumber ;

Answer 2

使用@MicSim回答：

SELECT  
    CASE 
        WHEN @UserRole = 1 THEN 1
        ELSE 0
    END AS [CanEdit],
        F.FundingStreamName       
FROM    FundingStream AS F
        RIGHT JOIN Projects AS P ON P.FundingStream = F.FundingStreamID 
WHERE   ProjectNumber = @ProjectNumber

再次感谢您的帮助！

SQL Case语句如何获取值而不管其他结果如何

2 个答案: