How do I do multiple CASE WHEN conditions using SQL Server 2008?

Question

What I\'m trying to do is use more than one CASE WHEN condition for the same column.

Here is my code for the query:

   SELECT   Url=\'\',
                    


        

Answer 1

There are two formats of case expression. You can do CASE with many WHEN as;

CASE  WHEN Col1 = 1 OR Col3 = 1  THEN 1 
      WHEN Col1 = 2 THEN 2
      ...
      ELSE 0 END as Qty

Or a Simple CASE expression

CASE Col1 WHEN 1 THEN 11 WHEN 2 THEN 21 ELSE 13 END

Or CASE within CASE as;

CASE  WHEN Col1 < 2 THEN  
                    CASE Col2 WHEN 'X' THEN 10 ELSE 11 END
      WHEN Col1 = 2 THEN 2
      ...
      ELSE 0 END as Qty

Answer 2

Just use this one, You have to use more when they are classes.

SELECT   Url='',
         p.ArtNo,
         p.[Description],
         p.Specification,
         CASE 
         WHEN 1 = 1 or 1 = 1 
            THEN 1 
         WHEN 2 = 2
             THEN 2
         WHEN 3 = 3
              THEN 3
          ELSE 0 
        END as Qty,
        p.NetPrice,
        [Status] = 0
  FROM  Product p (NOLOCK)

Answer 3

I had a similar but it was dealing with dates. Query to show all items for the last month, works great without conditions until Jan. In order for it work correctly, needed to add a year and month variable

declare @yr int
declare @mth int

set @yr=(select case when month(getdate())=1 then YEAR(getdate())-1 else YEAR(getdate())end)
set @mth=(select case when month(getdate())=1 then month(getdate())+11 else month(getdate())end)

Now I just add the variable into condition: ...

(year(CreationTime)=@yr and MONTH(creationtime)=@mth)

Answer 4

Its just that you need multiple When for a single case to behave it like if.. Elseif else..

   Case when 1=1       //if
   Then
    When 1=1              //else if
     Then.... 
    When .....              //else if
    Then 
    Else                      //else
   ....... 
     End