如何使用PHP将mysql数据转换为所需的json格式

Question

I have a question about using a MySQL Query to convert my data into a JSON Object. The Query I have is converting to a JSON Object,

I have learned using array() and trying to create a json which I can use in any mobile application.

mysql data is -

state_name      city_name  varient_name price

Uttar Pradesh   Lucknow     varient1    1202
Uttar Pradesh   Lucknow     varient2    1203
Uttar Pradesh   Lucknow     varient3    1204
Delhi           Faridabad   varient1    1206
Delhi           Faridabad   varient2    1207
Delhi           Faridabad   varient3    1208
Delhi           Saket       varient1    1207
Delhi           Saket       varient2    1208
Delhi           Saket       varient3    1209

and the response needed in the format -

{
    "states": [
        {
            "state_name": "Uttar Pradesh",
            "cities": [
                {
                    "city_name": "Lucknow",
                    "pricedata": [
                        {
                            "varient_name": "varient1",
                            "varient_price": "1201"
                        },
                        {
                            "varient_name": "varient2",
                            "varient_price": "1201"
                        },
                        {
                            "varient_name": "varient3",
                            "varient_price": "1203"
                        }
                    ]
                }
            ]
        },
        {
            "state_name": "Delhi",
            "cities": [
                {
                    "city_name": "Faridabad",
                    "pricedata": [
                        {
                            "varient_name": "varient1",
                            "varient_price": "1204"
                        },
                        {
                            "varient_name": "varient2",
                            "varient_price": "1205"
                        },
                        {
                            "varient_name": "varient3",
                            "varient_price": "1206"
                        }
                    ]
                },
                {
                    "city_name": "Saket",
                    "pricedata": [
                        {
                            "varient_name": "varient1",
                            "varient_price": "1207"
                        },
                        {
                            "varient_name": "varient2",
                            "varient_price": "1208"
                        },
                        {
                            "varient_name": "varient3",
                            "varient_price": "1209"
                        }
                    ]
                }
            ]
        }
    ]
}

Answer 1

$aR = array();
$req = mysqli_query("SELECT * FROM table");
while($row = mysqli_fetch_assoc($req))
{
    $aR[] = $row;
}
echo '<pre>'.print_r(json_encode($aR),1).'</pre>';