Retrieving Books By Given Author: XQuery Explained

[KataKoniK]

I have to write an XQuery that for example, "returns a list of books for a given author".

The "given author" in this case can be anything. Therefore, I was wondering what do I need to add to give the query someting, which in return, it will process it.

For example,

for $x in doc("a.xml")/Stuff
where $x/Author = [given author]
return $x/Book

 

[Sane]

If the "given author" can be anything, that means it doesn't need to meet a certain condition in order to be processed, correct? And therefore, you shouldn't need to condition it with a "where" statement.

Merely process the Author attribute as you need it. What is it exactly that you are trying to do?

 

[ravenprp]

In order to retrieve a list of books for a given author using XQuery, you will need to add a variable for the "given author" and use it in your query. This variable can be defined at the beginning of your query, for example:

let $author := [given author]

Then, you can use this variable in your where clause to filter the results by the given author:

for $x in doc("a.xml")/Stuff
where $x/Author = $author
return $x/Book

This will return a list of books where the author matches the given author variable. You can also use the variable in other parts of your query, such as in the return statement to specify which information you want to retrieve for the given author.

Overall, by adding a variable for the given author and using it in your query, you can easily retrieve a list of books for that specific author using XQuery.