On the php[architect] site they've posted a full article from their July 2018 issue sharing information about a new kind of data store in MySQL.

Do you work on projects where you begin coding before knowing what your data looks like? Or are you part of the vast majority of developers who have had little or no training in database theory, relational calculus, Structured Query Language, or sets? Could you be working on a project without a database administrator to set up relational tables, indexes, and schemas? Or are you tired of embedding ugly lines of SQL in your pristine PHP code? There is new hope for you.

In the article Dave Stokes (of MySQL/Oracle) covers the new native JSON data type that was added in MySQL 5.7 but enhanced in MySQL 8 as a document store. He shows how to use this new functionality from the command line, what a "document" is and how to install and use the X DevAPI PECL extension to make use of it from your PHP code.