Answer 1

"SQL++, an SQL-compatible query language developed at the University of California, San Diego, extends SQL with a few simple features that enable it to query data in the popular JSON format. The goal of SQL++ is to empower developers to create a new generation of applications, leveraging their existing SQL-based knowledge and tools."

source/tuto:
https://www.couchbase.com/sql-plus-plus-for-sql-users