Agnes has been using XQuery to design queries using path expressions. Her next project will involve multiple source documents and require more complicated criteria. She has heard that a FLWOR structure could be effective for such cases, and comes to you for assistance in developing a FLWOR structure query.
-Agnes is confused by the rules about how many of each type of clause are required in a FLWOR structure. You tell her that in a FLWOR structure, there must be exactly only one _____ clause.

Question

Agnes has been using XQuery to design queries using path expressions. Her next project will involve multiple source documents and require more complicated criteria. She has heard that a FLWOR structure could be effective for such cases, and comes to you for assistance in developing a FLWOR structure query. 
-Agnes is confused by the rules about how many of each type of clause are required in a FLWOR structure. You tell her that in a FLWOR structure, there must be exactly only one _____ clause.

Quizplus · Accepted Answer

The FLWOR structure stands for For-Let-Where-Order by-Return. It must have exactly one return clause, as this is where the query will output its results. The for, let, where, and order by clauses are optional, but there must be at least one of them for the query to be valid.

Agnes Has Been Using XQuery to Design Queries Using Path