Explain the syntax rule of XQuery language.

Question

What is The Rule of Three in C++? Please answer the following questions also -

1. What does copying an object mean?
2. What are the copy constructor and the copy assignment operator? When do I need to declare them myself?
3. How can I prevent my objects from being copied?

Answer 1

XQuery is written in FLWOR fashion which stands for: For, Let, Where, Order by, Return

An example of XQuery is:

for $x in doc("abc.xml")/abc_name
where $x/a>30
order by $x/b
return $x/c 

XQuery expression contains two parts: the Prolog and the Body. An XQuery query is made up of a prolog and a body. The XQuery body comprises of a sequence of expressions that specify the intended query result. A series of declarations and definitions that together create the required environment for query processing called the XQuery prolog.