I'm trying to make the result of one of my subqueries be used in another subquery but it doesn't work.
This is the query:
SELECT t.TenantName, 
    (SELECT SUM(Amount) 
     FROM tblTransaction 
     WHERE Amount > 0 
        AND TransactionDate >= '12/01/09' 
        AND TransactionDate <= '12/31/09'
        AND TenantID = t.ID 
        AND TransactionCode = trans.TransactionCode) AmountPaid, 
    (SELECT SUM(Amount) 
     FROM tblTransaction 
     WHERE tblTransaction.TransactionCode = trans.TransactionCode 
        AND tblTransaction.TenantID = t.ID) - AmountPaid AmountOwedTotal, 
    (SELECT SUM(Amount) 
     FROM tblTransaction 
     WHERE  tblTransaction.TransactionCode = trans.TransactionCode 
        AND tblTransaction.TenantID = t.ID
       AND Amount < 0 AND TransactionDate >= '12/01/09' 
        AND TransactionDate <= '12/31/09') AmountOwedThisMonth, 
   code.Description, trans.TransactionDate 
FROM tblTransaction trans 
   LEFT JOIN tblTenantTransCode code 
      ON code.ID = trans.TransactionCode
   LEFT JOIN tblTenant t 
      ON t.ID = trans.TenantID
WHERE trans.TransactionDate >= '12/01/09' 
   AND trans.TransactionDate <= '12/31/09' 
   AND trans.Amount > 0
Sorry it's so complicated.
Where I do (subquery) - AmountPaid the SqlServer complains AmountPaid isn't a valid column name. How can I get access to the result of it's subquery?