SQL Server built-in functions

By using SQL Server built-in functions and operators, you can do the following things with JSON text:

• Parse JSON text and read or modify values.
• Transform arrays of JSON objects into table format.
• Run any Transact-SQL query on the converted JSON objects.
• Format the results of Transact-SQL queries in JSON format.

JSON data type

The new json data type that stores JSON documents in a native binary format that provides the following benefits over storing JSON data in varchar/nvarchar:

• More efficient reads, as the document is already parsed
• More efficient writes, as the query can update individual values without - accessing the entire document
• More efficient storage, optimized for compression
• No change in compatibility with existing code

you can see example of JSON data type in SQL Server in here: JSON data in SQL Server