PHP json_encode 2 arrays - php

Question

I need to create a json with two (or more) arrays that can have other arrays inside. I did several tests, but I can never get a correct output. This is the output I would like to get to:
{
"servizi" : [
{"id": 1, "nomeservizio": "Menu","value": 1},
{"id": 2, "nomeservizio": "Prenotazione","value": 0}
],
"pietanze" : [
{"tipopietanza": "PANINI","PANINI" : [
{"id": 1, "nomepietanza": "Royal avec du fromage", "prezzo": 5.50, "ingredienti": "Hamburger di manzo, cetriolini sott'aceto, cheddar, cipolle, senape, ketchup"},
{"id": 2, "nomepietanza": "Big Belly Burger", "prezzo": 5.50, "ingredienti": "Hamburger di manzo, cipolla,senape, salsa worchester, prezzemolo, aglio, peperone, lattuga"}
]},
{"tipopietanza": "CONTORNI E STUZZICHINI", "CONTORNI E STUZZICHINI" :[
{"id":1, "nomepietanza": "Caprese", "prezzo": 4.00, "ingredienti": "Mozzarella"},
{"id":2, "nomepietanza": "Insalata", "prezzo": 3.50, "ingredienti": "Insalata"}
]}
]
}
I want to take the data from a database and this is the first part of the output where I get "servizi", now I want to get "pietanze" and put it like in the json I showed
<?php
$user = 'root';
$pass = '';
$db = 'taurosdb';
$connect = mysqli_connect("localhost", "root", "", "taurosdb");
$sql = "-query that takes me the "servizi"-";
$result = mysqli_query($connect, $sql);
$json_array = array();
while($row = mysqli_fetch_assoc($result))
{
$json_array[] = $row;
}
echo json_encode(array('servizi' => $json_array));
?>

Answer 1

Just make your array a variable so you can work with it. Instead of this:
echo json_encode(array('servizi' => $json_array));
You can say:
$my_big_array = ["servizi" => $json_array];
Then later on:
$my_big_array["pietanze"] = $some_other_data;
Then at the end you can output the JSON. Don't forget to set the Content-Type header.
header("Content-Type: application/json");
echo json_encode($my_big_array);