XQUERY If Then Else

Question

I have the following xml example, which I'm trying to xquery in BaseX.

<book>     <title>Book 1</title>     <price>15.99</price>   </book>  <book>     <title>Book 2</title>     <price>5.99</price>    </book>   <book>     <title>Book 3</title>     <price>5</price>    </book>

Basically it's a series of elements with a price tag. I'm trying to extract it with a tag to each depending on the price range, so for instance less then 10 would be cheap, then average, then premium.

Thanks in advance.

Answer 1

Here is an example, I assumed there is a books root element around the book elements:

declare namespace output = "http://www.w3.org/2010/xslt-xquery-serialization";

declare option output:method "xml";
declare option output:indent "yes";

<categories>
{
for $book in books/book
group by $cat := if ($book/price < 10) then 'cheap' else if ($book/price < 20) then 'average' else 'premium'
return
  <category name="{$cat}">{$book}</category>  
}
</categories>

Output is e.g.

<categories>
   <category name="average">
      <book>
         <title>Book 1</title>
         <price>15.99</price>
      </book>
   </category>
   <category name="cheap">
      <book>
         <title>Book 2</title>
         <price>5.99</price>
      </book>
      <book>
         <title>Book 3</title>
         <price>5</price>
      </book>
   </category>
</categories>