As a part from my new project, I'm using MySQL JSON field which was introduced in version 5.7, functions are described in https://dev.mysql.com/doc/refman/5.7/en/json-functions.html Creating JSON data is pretty simple like:
As you can see Create Table syntax is same, difference is in `custom_data` JSON . So let's insert some data to it.

And lets assume that we want to filter data in JSON field. Result is:
Or if we want to check existence of sub element:
Result is:
And one more example for extracting value from JSON:

It's look pretty easy, right ? :)