Our first implementation of JSONiq was done in the Zorba NoSQL processor, which is developed jointly between Oracle, 28msec, and the FLWOR Foundation. The home page is http://zorba.io/ and a sandbox is available on http://try.zorba.io/. You can run most of the queries shown in the examples of this book in this sandbox (not the ones accessing collections).

28msec provides a platform called 28.io, which is specifically tailored for executing JSONiq queries against an existing MongoDB database. You can run all example queries in the Try-It-Now sandbox at http://28.io/, in which the collections faq and answers are prepopulated with lots of data and additional sample queries.

If you obtained this book shortly after its publication, you should be aware that the array unboxing syntax may not be released yet, as it is recent. If array unboxing does not work, try $a() instead of $a[] and $a(2) instead of $a[][2].