By default, AsterixDB supports two languages:

• AQL 
• SQL++: SQL for JSON

For example, to return the subtree under the root node of a dataset tree, your query statement would be something such as the following:

SELECT VALUE user
FROM UserType user;

To return subtree under a node that satisfied a different predicate:

SELECT VALUE user
FROM UserType user
WHERE array_count(user.friendIds) = 1

There is a lot to process and a lot of built-in functions available with AsterixDB that are beyond the scope of this book. We suggest you follow the documentation and create your own schema. Attached below after Further reading in this PDF.