Question

I have 2 tables:

AppDetailFee table has AppID (PK), TypeID, Amount
AppDetail table has AppID (PK)   

I join both tables on AppID and I need to check the following for TypeID and amount. There are 3 scenarios:

If TypeID = 6 and Amount = 0 then  print appid and amount zero
If typeID = 6 and amount <> 0  - bypass and do not print
When TypeID <> 6 then print zero

Below is the code that I used, btu I get a result of all the rows that are not equal to zero with an amount of zero.

Any help would be appreciated.
Thanks

SELECT  ad.AppID
      , MAX(case when (adf.TypeID = 6 AND adf.Amount = 0) then 0 
                 when (adf.TypeID = 6 AND adf.Amount <> 0) then Adf.Amount
       ELSE 0 END) AS FeeAmount

FROM         
      AppDetail AS ad   

inner join  AppDetailFee adf ON
      ad.AppID = adf.AppID 

WHERE  adf.Amount =0

Answer 1

You have a WHERE clause that is removing everything that does not meet the criteria:

WHERE  adf.Amount =0

Try removing that and running your query:

SELECT  ad.AppID
      , MAX(case when (adf.TypeID = 6 AND adf.Amount = 0) then 0 
                 when (adf.TypeID = 6 AND adf.Amount <> 0) then Adf.Amount
                 else 0 END) AS FeeAmount
FROM  AppDetail AS ad   
inner join  AppDetailFee adf ON
      ad.AppID = adf.AppID 
group by ad.AppID

You are also missing the GROUP BY clause on your query.