Unql: nosql Query Language released by couchdb and SQLite

CouchdbAndSQLiteDevelopers jointly developed a set of query language specifications for nosql, named unql (pronounced as "uncle"), similar to the SQL language specifications of relational databases,UnqlIt is mainly positioned in the standard query of document nosql databases.

In fact, couchdb authors Damien Katz and SQLite authors Richard hipp have been developing a unified language that supports document database queries. Katz pointed out that "we realized that compared with the SQL language of relational databases, nosql also needs such a unified query language interface to regulate the current chaotic situation"
Hipp adds that "unql is based on our existing experience in the SQL language. Unlike SQL, it provides syntax support for unstructured data and adds self-descriptive data"

The syntax tree diagram is as follows: