Question

I have the following function:

CREATE FUNCTION fGetTransactionStatusLog (     @TransactionID  int ) RETURNS varchar(8000) AS   BEGIN   declare StatusChanges cursor for     select  NewStatusID, FirstName + ' ' + LastName AS UserName, Stamp, CAST(Notes AS varchar(8000)) AS Notes       from TransactionStatusChanges tsc         left join Users us ON tsc.UserID = us.UserID       where TransactionID = @TransactionID ORDER BY StatusNum  declare @output varchar(8000)  declare @NewStatusID char(2) declare @UserName varchar(255) declare @Stamp datetime declare @Notes varchar(8000)  set @output = ''  OPEN StatusChanges   FETCH NEXT FROM StatusChanges INTO @NewStatusID, @UserName, @Stamp, @Notes   WHILE @@FETCH_STATUS = 0   BEGIN      set @output = @output + RTRIM(CAST(@Stamp AS varchar(30))) + ': ' + @NewStatusID + ' by ' + @UserName +  CHAR(13) + CHAR(10)      IF @Notes IS NOT NULL     BEGIN         set @output = @output + '---' + @Notes +  CHAR(13) + CHAR(10)     END      FETCH NEXT FROM StatusChanges INTO @NewStatusID, @UserName, @Stamp, @Notes   END CLOSE StatusChanges DEALLOCATE StatusChanges  RETURN @output  END 

Now, that function returns exactly what I want for the Transactions that don’t have any Notes in any records… For transaction that have at least one record in TransactionStatusChanges with a non-NULL Notes field, I get NULL.

I don’t quite get it, since I AM checking that @Notes is not NULL before concatting it.

Any ideas?

NOTE: I’m using varchar(8000) because I can’t use text inside Functions.

Answer 1

One of these is NULL

   set @output = @output + RTRIM(CAST(@Stamp AS varchar(30))) + ': ' + @NewStatusID + ' by ' + @UserName +  CHAR(13) + CHAR(10) 

Also, you can make your code simpler by using ISNULL or COALESCE to handle columns which contain NULLs

CREATE FUNCTION fGetTransactionStatusLog (     @TransactionID  int ) RETURNS varchar(8000) AS   BEGIN   declare @output AS varchar(8000)  select @output = ISNULL(@output, '')         + ISNULL(RTRIM(CAST(Stamp AS varchar(30))), '<NULL>')         + ISNULL(NewStatusID, '<NULL>') + ' by '         + ISNULL(FirstName + ' ' + LastName, '<NULL>') + CHAR(13) + CHAR(10)         + ISNULL('---' + Notes +  CHAR(13) + CHAR(10), '') from TransactionStatusChanges tsc left join Users us ON tsc.UserID = us.UserID where TransactionID = @TransactionID ORDER BY StatusNum  RETURN @output  END