Question

Here is a simplified version of a stored procedure I am trying to write in SQL Server 2005.

My question is this:

I have declared a variable @docid to which I want to assign the results of a query as I Iterate through my cursor, if there is not an exact match, then I want to run another query and try for the next best match.

I tried putting in a test that says IF @docid IS NULL then BEGIN [second query]. This does not work since the variable @docid will not be Null it will just retain the previous value until the conditions for the first query are met and it is assigned a new value.

So how can I say “If I try to assign a docid to the variable @docid, but there is no match based on the conditions in the query then run the next query instead or set @docid=''"? Any help would be appreciated. Thanks

declare @docid bigint,
        @account varchar(30)

While @@fetch_status=0
BEGIN
   Select @Docid=Docid
   FROM printdata 
   WHERE Account=@account

   IF @docid Is Null --Docid Is never Null once assigned a value
   BEGIN
     Select @Docid=Docid
     FROM printdata 
     WHERE balance=@balance
  END

Answer 1

Well, I would just first initialize @docid to NULL – then it will be NULL if nothing is found:

declare @docid bigint,
        @account varchar(30)

While @@fetch_status=0
BEGIN
   SET @docid = NULL

   SELECT @Docid = Docid
   FROM printdata 
   WHERE Account = @account

   IF @docid IS NULL  --  @Docid *WILL* be NULL now if nothing is found!
   BEGIN
     SELECT @Docid = Docid
     FROM printdata 
     WHERE balance = @balance
  END