JSONiq

JSONiq is a query language designed for querying, transforming, and constructing JSON data. It extends the ideas of XQuery to the JSON data model, providing a unified approach to extract information, perform transformations, and produce JSON documents as results.

The language builds on FLWOR expressions and other familiar XQuery concepts, adapted for JSON. It offers object and array constructors, as well as JSON-specific functions and operators to support filtering, joining, grouping, and sorting. JSONiq treats JSON values—such as null, booleans, numbers, strings, arrays, and objects—as first-class values, enabling expressive data querying and manipulation within a declarative, functional style.

Interoperability and implementations vary, but JSONiq is designed to work with JSON data stored in databases, file systems, or transmitted through APIs. Several engines implement JSONiq or JSONiq-like features, with Zorba being a notable open-source reference implementation. Some XML and XQuery processors also provide JSON support through extensions or side modules, reflecting JSONiq’s lineage from XQuery.

Typical use cases include data integration, API data processing, transformation pipelines, and ETL workflows that involve JSON data. JSONiq enables developers to query, reshape, and normalize JSON data to produce clean JSON outputs or to feed JSON into downstream systems, analytics, or data stores.

There is no single formal standards body governing JSONiq; it has evolved through community-driven specifications and multiple implementations. This has produced a practical, widely used approach to querying JSON, distinct from but related to XQuery and other JSON-processing tools.