Question

I’m working with SQL, and I can’t seem to figure this out for the life of me.

I have a local variable in my stored procedure called @curType. I have two tables, DTXR and DP. DP contains the columns type and programID. DTXR contains the columns programID and QEI. The stored procedure is passed the QEI, and I need to get the type from the table DP and assign it to the local variable @curType.

So, I currently have

select @curType = [Type] From DP d 
       Join DTXR x on d.ProgramId = x.ProgramID
       where x.QEI = @p_QEI.  

@p_QEI is the variable passed into the stored procedure.

The problem I’m running in to is this doesn’t seem to set @curType. It works if I manually set the program id like this:

select @curType = [Type] from DP Where DP.ProgramId = 120

But the join statement seems to be setting @curType to null.

Answer 1

Actually, this should work. I would check to make sure that the following even returns anything at all (and if it does, what is the first result back?):

   select [Type] From DP d 
   Join DTXR x on d.ProgramId = x.ProgramID
   where dtxr.QEI = @p_QEI

That should be the problem, as here is a fiddle proving that a join does nothing different