Create GUID() based on Business key combination

Question

Hi All,
We have a requirement to create GUID for a Business Key, Please check the below example.
SELECT ID ,AB, (CASE WHEN RANK() OVER(PARTITION BY ID ORDER BY AB ) = 1 THEN NEWID() ELSE NULL END ) AS GID 
INTO #FIN 
FROM (
SELECT 1 AS ID,'A' AS AB UNION ALL 
SELECT 1,'B' AS AB UNION ALL 
SELECT 2,'A' AS AB UNION ALL 
SELECT 2 ,'B' AS AB UNION ALL 
SELECT 3 ,'A' AS AB ) A 
SELECT ID,AB,(SELECT GID FROM #FIN B WHERE B.ID = A.ID AND GID IS NOT NULL) AS GID  FROM #FIN A
I get same GUIDs for row 1 & 2, another Guid for 3 & 4. Can this be done without using a temp table?
Rajkumar

Answer 1

try below
select ID,AB,max(convert(varchar(50),GID)) over(partition by id)
from
(SELECT ID ,AB, (CASE WHEN RANK() OVER(PARTITION BY ID ORDER BY AB ) = 1 THEN NEWID() ELSE NULL END ) AS GID
--INTO #FIN
FROM (
SELECT 1 AS ID,'A' AS AB UNION ALL
SELECT 1,'B' AS AB UNION ALL
SELECT 2,'A' AS AB UNION ALL
SELECT 2 ,'B' AS AB UNION ALL
SELECT 3 ,'A' AS AB ) A
) a1
Thanks
Saravana Kumar C