Here are a few things that we can use / read about MySQL and JSON.

Small benchmark tests of reading 20000

Krasimir Tsonev has made a small benchmark tests of reading 20000 from a MySQL db and from a JSON file.

I’m gonna just put the *end* results. You can read all the article on Krasimir’s blog about MySQL vs JSON file data storing benchmark results.

MySQL

ab -n 30 -c 30 http://localhost/mqsql.php
Concurrency Level:      30
Time taken for tests:   30.518 seconds

JSON

ab -n 30 -c 30 http://localhost/json.php
Concurrency Level:      30
Time taken for tests:   3.384 seconds

MySQL query to JSON

The MySQL query

SELECT 
     CONCAT("[",
          GROUP_CONCAT(
               CONCAT("{username:'",username,"'"),
               CONCAT(",email:'",email),"'}")
          )
     ,"]") 
AS json FROM users;

The JSON result

[
     {username:'mike',email:'[email protected]'},
     {username:'jane',email:'[email protected]'},
     {username:'stan',email:'[email protected]'}
]

Got this from http://www.thomasfrank.se/mysql_to_json.html.