Multiple conditional Where clause

Question

I currently have a query that will pull a bunch of information from my database based on whatever where condition that I want to use.

declare @C         


        

Answer 1

With help from the link that @Norman posted I figured it out. I wanted to post my solution for others to see.

declare @CaseNum varchar(MAX),
        @ImportId varchar(MAX)


set @CaseNum = ''
set @ImportId = ''
----------------------------------------------------------------------------

If(@CaseNum = '')    --Sets the parameter to NULL for COALESCE to work
Begin
    Select @CaseNum = NULL
End

If(@ImportId = '')   --Sets the parameter to NULL for COALESCE to work
Begin
    Select @ImportId = NULL
End

--------------------
   query in here
--------------------

where
    gr.[CaseNum] = COALESCE(@CaseNum, gr.[CaseNum])
    and im.ImportId = COALESCE(@ImportId, im.ImportId)

This solution allows the query to use just a single parameter or all at the same time.