FLWOR is an acronym for the "For, Let, Where, Order by, Return".
The for clause is used to select all book elements under the
bookstore element into a variable called $x.
The where clause selects only the book elements with a
price element with a value greater than 30.
The order by clause define the sort-order. Will be
sort by the title element.
The return clause specify what should be returned.
Here it returns the title elements.
The result of the XQuery expression above will be like this: