How to convert result table to JSON array in MySQL

I'd like to convert result table to JSON array in MySQL using preferably only plain MySQL commands. For example with query

SELECT name, phone FROM person;

| name | phone |
| Jack | 12345 |
| John | 23455 |

the expected JSON output would be

[
  {
    "name": "Jack",
    "phone": 12345
  },
  {
    "name": "John",
    "phone": 23455
  }
]

Is there way to do that in plain MySQL?

EDIT:

There are some answers how to do this with e.g. MySQL and PHP, but I couldn't find pure MySQL solution.

Solution 1:

New solution:

Built using Your great comments, thanks!

SELECT JSON_ARRAYAGG(JSON_OBJECT('name', name, 'phone', phone)) from Person;

Old solution:

With help from @Schwern I managed to put up this query, which seems to work!

SELECT CONCAT(
    '[', 
    GROUP_CONCAT(JSON_OBJECT('name', name, 'phone', phone)),
    ']'
) 
FROM person;

Solution 2:

You can use json_object to get rows as JSON objects.

SELECT json_object('name', name, 'phone', phone)
FROM person;

This won't put them in an array, or put commas between them. You'll have to do that in the code which is fetching them.

Solution 3:

If you're stuck on MySQL 5.6 like me, try this:

SELECT
    CONCAT(
       '[',
       GROUP_CONCAT(
           CONCAT(
               '{"name":"', name, '"',
               ',"phone":"', phone, '"}'
           )
       ),
       ']'
    ) as json
FROM person

Solution 4:

There are two "group by" functions for JSON called json_arrayagg, json_objectagg.

This problem can be solved with:

SELECT json_arrayagg(
    json_merge(
          json_object('name', name), 
          json_object('phone', phone)
    )
) FROM person;

This requires MySQL 5.7+.

Solution 5:

If u need a nested JSON Array Object, u can join JSON_OBJECT with json_arrayagg as below:

{
    "nome": "Moon",
    "resumo": "This is a resume.",
    "dt_inicial": "2018-09-01",
    "v.dt_final": null,
    "data": [
        {
            "unidade": "unit_1",
            "id_unidade": 9310
        },
        {
            "unidade": "unit_2",
            "id_unidade": 11290
        },
        {
            "unidade": "unit_3",
            "id_unidade": 13544
        },
        {
            "unidade": "unit_4",
            "id_unidade": 13608
        }
    ]
}

U cand do like this:

CREATE DEFINER=`root`@`localhost` PROCEDURE `get_lst_caso`(
IN `codigo` int,
IN `cod_base` int)
BEGIN

    DECLARE json TEXT DEFAULT '';

    SELECT JSON_OBJECT(
        'nome', v.nome, 
        'dt_inicial', v.dt_inicial, 
        'v.dt_final', v.dt_final, 
        'resumo', v.resumo,
        'data', ( select json_arrayagg(json_object(
                                'id_unidade',`tb_unidades`.`id_unidade`,
                                'unidade',`tb_unidades`.`unidade`))
                            from tb_caso_unidade
                                INNER JOIN tb_unidades ON tb_caso_unidade.cod_unidade = tb_unidades.id_unidade
                            WHERE tb_caso_unidade.cod_caso = codigo)
    ) INTO json
    FROM v_caso AS v
    WHERE v.codigo = codigo and v.cod_base = cod_base;
    
    SELECT json;
    
END