SQL查询：如果x = 1则y选择所有位置

Question

I want to select all columns however if fuel = 1 then start date > '1 oct 2013' else if fuel = 0 then start date > '1 september'.

Using SQL server 2005.

I tried this..

SELECT * FROM   EntitlementEpisode
WHERE
    IF EnFuel = 1
        THEN
            IF
                BEGIN
                    [EnEpisodeStart] > 
                    (SELECT TOP 1 [BeYearStart] 
                    FROM [BenefitYear] ORDER BY [BeId] desc)
                END
            ELSE IF EnFuel = 0
       THEN
            IF
                 BEGIN
                      [EnEpisodeStart] > 
                      CONVERT(VARCHAR(30), '1 OCT' + YEAR(GETDATE()))
            END

Is this the right way of going about it?

Answer 1

Use the strength of the binary operators...!

SELECT * 
FROM   EntitlementEpisode
WHERE
   (EnFuel=1 AND EnEpisodeStart] > 
                (SELECT TOP 1 [BeYearStart] 
                FROM [BenefitYear] ORDER BY [BeId] desc))

   OR

   (EnFuel=0 AND [EnEpisodeStart] > 
                  CONVERT(VARCHAR(30), '1 OCT' + YEAR(GETDATE())))

Answer 2

How about something like

SELECT  * 
FROM    EntitlementEpisode
WHERE   (EnFuel = 1 AND [EnEpisodeStart] > (SELECT TOP 1 [BeYearStart] FROM [BenefitYear] ORDER BY [BeId] desc)
OR      (EnFuel = 0 AND [EnEpisodeStart] > CONVERT(VARCHAR(30), '1 OCT' + YEAR(GETDATE())))