Question

I have a table like the following in SQL Server 2008

  AMID                TierLevel
 --------            -------------
  999                 GOLD
  1000                SILVER   
  1000                GOLD
  1000                PLATINUM
  1000                BRONZE
  1001                GOLD
  1001                SILVER
  1002                SILVER
  1003                GOLD

Now I want to Update this table like the following

  AMID                TierLevel
 --------            -------------
  999                 GOLD
  1000               PLATINUM  
  1000               PLATINUM
  1000               PLATINUM
  1000               PLATINUM
  1001                GOLD
  1001                GOLD
  1002                SILVER
  1003                GOLD

Here the conditions are

• I want unique Tier value for the same AMID, and the Tier values should be selected in priority base like

  1. PLATINUM
  2. GOLD
  3. SILVER
  4. BRONZE

• It means if it is having the highest one present in its Tier values then select that. Like I shown in the second table, Platinum for 1000 and Gold for 1001..

please help me with this

Thanks,
Harry

Answer 1

I would do this using a temporary table to store the rank of each Tier:

DECLARE @Rank TABLE (ID INT NOT NULL PRIMARY KEY, Name VARCHAR(10) NOT NULL)
INSERT @Rank VALUES (1, 'PLATINUM'), (2, 'GOLD'), (3, 'SILVER'), (4, 'BRONZE')

;WITH T AS
(   SELECT  AMID, TierLevel, MIN(ID) OVER(PARTITION BY AMID) [MinID]
    FROM    #T
            INNER JOIN @Rank
                ON Name = TierLevel
)
UPDATE  T
SET     TierLevel = Name
FROM    T
        INNER JOIN @Rank
            ON ID = MinID
WHERE   TierLevel <> Name

---

This was done using the following sample data:

CREATE TABLE #T (AMID INT, TierLevel VARCHAR(10))
INSERT #T VALUES 
    (999, 'GOLD'), 
    (1000, 'SILVER'), 
    (1000, 'GOLD'), 
    (1000, 'PLATINUM'), 
    (1000, 'BRONZE'),
    (1001, 'GOLD'),
    (1001, 'SILVER'),
    (1002, 'SILVER'),
    (1003, 'GOLD')