SQL Trick.

We have a new programmer in our office and she created this query. The thing that blew my mind was the set using in effect a list. I thought you could only update a single field on a select but it works.

Update PLNREQ a
   Set (PPLANIB,
PITCLS) =
          (Select b.PLANIB, 
                  b.ITCLS
             From ITEMBL b
             Where a.PITEM = b.ITNBR And               
                   a.PWH   = b.HOUSE)                  
  Where a.PPLANIB = ' ' And                                            
         a.PITCLS = ' '  

The trick seems to be putting the brackets around the list of fields to update.

Anybody seen this before? SQL never ceases to amaze me.