MYSQL直接輸出JSON

透過SQL語法直接使用MYSQL輸出JSON

下的語法 

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

輸出結果

[
     {username:'tommy',email:'tommy@tommysplace.com'},
     {username:'jane',email:'jane@examples.com'},
     {username:'jack',email:'jack@jiford.com'}
]