that example is intending to produce a single column result that concatenates two fields into a comma-separated string, e.g. &quot;your name, you@somesite.com&quot;.<p>I think jumping into that example directly is probably kind of disorienting.  The SQL in that string is a little bit weird&#x2F;contorted just to illustrate, &quot;it&#x27;s text, do whatever you want!&quot;.    I also wrote that example like ten years ago.