Example of grouping and counting in XQuery

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Example of grouping and counting in XQuery

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Last edited Jul 28, 2017

Created on Jul 28, 2017

This example demonstrates how to group XML elements by an attribute value and count the grouped items using XQuery 3.1’s `group by` clause. It defines a small in-memory `<books>` dataset with five book titles categorized by `class` attributes (fiction or nonfiction). The query iterates over each `<book>`, extracts the text content as titles, and groups them by class, then returns a new element named after each class containing an ordered, numbered list of titles. The implementation relies on XQuery’s `element` constructor and `count` clause to generate the output, with titles sorted alphabetically using `order by`.

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