Using PHP multidimensional arrays to convert MySQL to JSON

Question

Here\'s my table structure.

I\'m trying to convert MySQL to nested JSON, but am having trouble figuring out how to build the multidimensional array in PHP.

T

Answer 1

I started from Ian Mustafa reply and I figure out to solve the problem of each loop erasing the previous array.

It's an old thread but I think this could be useful to others so here is my solution, but based on my own data structure (easy to figure out how to adapt it to other structures I think) :

$usersList_array =array();
$user_array = array();
$note_array = array();

$fetch_users = mysqli_query($mysqli, "SELECT ID, Surname, Name FROM tb_Users WHERE Name LIKE 'G%' ORDER BY ID") or die(mysqli_error($mysqli));
while ($row_users = mysqli_fetch_assoc($fetch_users)) {
    $user_array['id'] = $row_users['ID'];
    $user_array['surnameName'] = $row_users['Surname'].' '.$row_users['Name'];
    $user_array['notes'] = array();

    $fetch_notes = mysqli_query($mysqli, "SELECT id, dateIns, type, content FROM tb_Notes WHERE fk_RefTable = 'tb_Users' AND fk_RefID = ".$row_users['ID']."") or die(mysqli_error($mysqli));
    while ($row_notes = mysqli_fetch_assoc($fetch_notes)) {
        $note_array['id']=$row_notes['id'];
        $note_array['dateIns']=$row_notes['dateIns'];
        $note_array['type']=$row_notes['type'];
        $note_array['content']=$row_notes['content'];
        array_push($user_array['notes'],$note_array);
    }

    array_push($usersList_array,$user_array);
}

$jsonData = json_encode($usersList_array, JSON_PRETTY_PRINT);


echo $jsonData; 

Resulting JSON :

[
{
    "id": "1",
    "surnameName": "Xyz Giorgio",
    "notes": [
        {
            "id": "1",
            "dateIns": "2016-05-01 03:10:45",
            "type": "warning",
            "content": "warning test"
        },
        {
            "id": "2",
            "dateIns": "2016-05-18 20:51:32",
            "type": "error",
            "content": "error test"
        },
        {
            "id": "3",
            "dateIns": "2016-05-18 20:53:00",
            "type": "info",
            "content": "info test"
        }
    ]
},
{
    "id": "2",
    "cognomeNome": "Xyz Georg",
    "notes": [
        {
            "id": "4",
            "dateIns": "2016-05-20 14:38:20",
            "type": "warning",
            "content": "georg warning"
        },
        {
            "id": "5",
            "dateIns": "2016-05-20 14:38:20",
            "type": "info",
            "content": "georg info"
        }
    ]
}
]