Question

This query works fine before I try to grab a count of how many Payments (trans_key) there are against each account (ACCT).

Cannot perform an aggregate function on an expression containing an aggregate or a subquery.

SELECT CONVERT(VARCHAR,D.ACCT) ClientReference,
    ISNULL((SELECT S.SD_DATA 
            FROM SDDATA AS S 
            WHERE S.DEBT_KEY=D.DEBT_KEY AND S.SD_KEY=36),' ') Division,
    REPLACE(RTRIM(DB.FNAME)+' '+RTRIM(DB.LNAME),',',' ') AccountHolder,
    CONVERT(VARCHAR,D.DOR,101) ListedDate,
    ISNULL((SELECT SA.SD_DATA 
            FROM SDDATA AS SA 
            WHERE SA.DEBT_KEY=D.DEBT_KEY 
                AND SA.SD_KEY=2),' ') AssignmentType,
    CONVERT(VARCHAR,D.BAL) CurrentBalance,
    CONVERT(VARCHAR,D.ASSIGNED) PlacementBalance,
    CONVERT(VARCHAR,isnull((SELECT -1*SUM(TD.DIST_AMT) 
                            FROM TRANSDIST AS TD,TRANS AS T,TRANS_CODE AS TC 
                            WHERE T.DEBT_KEY=D.DEBT_KEY 
                                AND TD.TRANS_KEY=T.TRANS_KEY  
                                AND TC.TRANS_CODE=T.TRANS_CODE 
                                AND TC.TRANS_BILL=1),0)) AmountRecovered,
    CONVERT(VARCHAR,isnull((SELECT (-1*SUM(TD.DIST_AMT)+SUM(DIST_NET)) 
                            FROM TRANSDIST AS TD,TRANS AS T,TRANS_CODE AS TC 
                            WHERE T.DEBT_KEY=D.DEBT_KEY 
                                AND TD.TRANS_KEY=T.TRANS_KEY  
                                AND TC.TRANS_CODE=T.TRANS_CODE 
                                AND TC.TRANS_BILL=1),0)) AmountApplied,
    CONVERT(VARCHAR,isnull((SELECT (-1*SUM(DIST_NET)) 
                            FROM TRANSDIST AS TD,TRANS AS T,TRANS_CODE AS TC 
                            WHERE T.DEBT_KEY=D.DEBT_KEY 
                                AND TD.TRANS_KEY=T.TRANS_KEY  
                                AND TC.TRANS_CODE=T.TRANS_CODE 
                                AND TC.TRANS_BILL=1),0)) SMAFees,
    COUNT((select trans_key from trans)) as Payments 
FROM DEBT AS D,DEBTOR AS DB,STATUS AS ST
WHERE ST.STAT_KEY=D.STAT_KEY
    AND DB.DEBTOR_KEY=D.DEBTOR_KEY
    AND D.CLIENT_KEY =43 
    AND ST.CATEGORY='A'

When messing around with the count aggregate function I was able to grab soem data, but not the correct count. It was just giving me the count of all ‘Payments’ inside the table not the amount for each ACCT.

Answer 1

I feel like your query is written in a very strange way that will make it difficult to debug. A few thoughts:

• Stop Converting everything you are selecting (at least until you get
  the results you want). This will make your code more concise and
  easier to debug

• If possible, stop with the subqueries in your select statement. For example:

  ISNULL((SELECT SA.SD_DATA
  FROM SDDATA AS SA
  WHERE SA.DEBT_KEY=D.DEBT_KEY
  AND SA.SD_KEY=2),’ ‘) AssignmentType,

can be converted to

ISNULL(SA.SD_DATA,' ')
...
...
FROM DEBT AS D
LEFT JOIN SDDATA AS SA 
ON sa.DEBT_KEY = d.DEBT_KEY

• Stop using implied joins

• Read up on how GROUP BY works with aggregate functions.

This isn’t a solution for your exact problem, but you need to get this query into a workable state and do some basic research if you want to resolve this issue.