The number of fields that can be included in the query's use of ISNULL and NULLIF is not limited to two. You can just keep concatenating an ISNULL function, and then NULLIF the entire concatenation, and thus have as many fields as you need. They just all need to be strings, or alternately, CAST-ed or CONVERT-ed to strings.
Steve (aka sgmunson) 🙂 🙂 🙂
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