XQuery? ???? ?? ?? ??? ??? ????. XQuery? XML ?? ??? SQL? ?????? ??? ?? ??? ?????.
XQuery? XML ???? ??? ??????? ???? XML ???? ??? ? ?? ?? ???? ????? ???????.
XQuery ?? ???
XQuery? ????? ???? XQuery ??, ?? ? ??? ??? XML ????? ???.
XQuery ?? ?
for $x in doc("books.xml")/bookstore/book returnif ($x/@category="CHILDREN") then <child>{data($x/title)}</child> else <adult>{data($x/title)}</adult>
"If-Then-Else" ??? ?????. if ??? ?? ??? ?????. else? ????? "else ()"? ?????.
? ?? ??:
<adult>Everyday Italian</adult> <child>Harry Potter</child> <adult>Learning XML</adult> <adult>XQuery Kick Start</adult>