SQL to find only data in a table with no matching records

Question

I would like to find data in a table with no matching records based on two fields (ContractState, TransID).

For instance, assume this data set (in reality, all data sets contain hundreds of records, I'm just including a few):

AccountNbr  ContractState   TransID     Product
3335477     AL              80079       DPPO, DHMO
3335477     AL              80080       PPO
3335477     AR              80079       DPPO, DHMO
3335477     AR              80080       PPO

This should return 0 records, because there are 2 records for AL (one for each TransID) and 2 records for AR.

However, given the following data set:

AccountNbr  ContractState   TransID     Product
3335477     AL              80079       DPPO, DHMO
3335477     AL              80080       PPO
3335477     DE              80079       DHMO
3335477     WA              80080       DHMO

I would like to return only the following data set:

AccountNbr  ContractState   TransID     Product
3335477     DE              80079       DHMO
3335477     WA              80080       DHMO

because for each state, there is only 1 TransID.

I have this code, but it also includes records with matching data:

SELECT 
   'tblSQLContractState' as TableName, 
   TransID, 
   ContractState, 
   Product, 
   COUNT(*) AS [NumOfMessage]
FROM tblSQLContractState  
WHERE   TransID IN (80079, 80080)
GROUP BY 
   TransID, 
   ContractState, 
   Product
HAVING COUNT(*) = 1

Answer 1

Use window functions. For the data you provided, this should work:

select cs.*
from (select cs.*,
             count(*) over (partition by AccountNbr, ContractState) as cnt
      from tblSQLContractState cs
      where TransID IN (80079, 80080)
     ) cs
where cnt = 1;

Answer 2

You can use a NOT EXISTS to select records where there is another record with this TransId but not with this ContractState :

SELECT 
   'tblSQLContractState' as TableName, 
    cs.AccountNbr,  cs.ContractState, cs.TransID,  cs.Product
FROM tblSQLContractState cs
WHERE   cs.TransID IN (80079, 80080)
AND NOT EXISTS                                  -- no other record
(
    SELECT 1 FROM tblSQLContractState cs2
    WHERE cs2.TransID <> cs.TransID             -- with other TransId
      AND cs2.ContractState = cs.ContractState  -- and this  ContractState
)

NOT EXISTS is quite efficient in SQL-Server and can be modified/extended easily. Another advantage is that you can select all columns as opposed to a GROUP BY .

Answer 3

Your query is close. But you want one result row per ContractState - and it's also this attribute you want to know the number of records (aggregate COUNT(*) ) for. So remove Product and TransID from the GROUP BY clause.

As it's only combinations with a row count of 1 you want to show, you can use MIN(Product) or MAX(Product) to get the one product in question. Same for TransID .

SELECT 
   'tblSQLContractState' as TableName, 
   MAX(TransID) AS TransID, 
   ContractState, 
   MAX(Product) AS Product, 
   COUNT(*) AS [NumOfMessage]
FROM tblSQLContractState  
WHERE   TransID IN (80079, 80080)
GROUP BY ContractState
HAVING COUNT(*) = 1;

Gordon's answer is more more straight-forward and more of general use. Just the natural way to solve this in my opinion. I simply wanted to show that your query was very close :-)

UPDATE: Tim's answer is also very good. (It wasn't there when I typed mine.) He is right; all you want to know is whether there exists another record for the ContractState, so an exists clause is appropriate.