mysql 到 json 使用 php。 嵌套对象

Question

Good Afternoon, I am trying to get these results into arrays in PHP so that I can encode them into json objects and send them to the client. The results of the query look like this:

   id   name    hours   cat status
3bf JFK Int 24  pass    open
3bf JFK Int 24  std closed
3bf JFK Int 24  exp open
5t6 Ohm CA  18  pass    closed
5t6 Ohm CA  18  std closed
5t6 Ohm CA  18  std2    open
5t6 Ohm CA  18  exp open
...

I would like for the json objects to look like this:

{ "id": "3bf", "name": "JFK Int", "cats":
    { [ { "cat": "pass", "status": "open" },
        { "cat": "std", "status": "closed" },
        { "cat": "exp", "status": "open" } ] }
{ "id": "5t6", "name": "Ohm CA", "cats":
    { [ { "cat": "pass", "status": "closed" },
        { "cat": "std", "status": "closed" },
        { "cat": "std2", "status": "open" } ],
        { "cat": "exp", "status": "open" } ] }

I have succesfully connected to mysql and exported using json_encode using flat tables but this part I do not know how to do in PHP. Thanks.

This is the code that I have. This returns an array of json objects but it is flat, not nested:

$SQL = "SELECT id, name, hours, cat, status FROM bwt.vewPortCats";

$result = mysql_query($SQL);

$arr = array();
    while ($row = mysql_fetch_assoc($result)) {
        $arr[] = $row;}

$json = json_encode($arr);

echo $json;

The data itself is from a view that combines the tables ports and cats.

Answer 1

what you could do (sorry, not the best code I could write... short on time, ideas, and energy ;-) is something like this (I hope it still conveys the point):

$SQL = "SELECT id, name, hours, cat, status FROM bwt.vewPortCats";

$result = mysql_query($SQL);

$arr = array();
    while ($row = mysql_fetch_assoc($result)) {

        // You're going to overwrite these at each iteration, but who cares ;-)
        $arr[$row['id']]['id'] = $row['id'];
        $arr[$row['id']]['name'] = $row['name'];

        // You add the new category
        $temp = array('cat' => $row['cat'], 'status' => $row['status']);

        // New cat is ADDED
        $arr[$row['id']]['cats'][] = $temp;
    }


$base_out = array();

// Kind of dirty, but doesn't hurt much with low number of records
foreach ($arr as $key => $record) {
    // IDs were necessary before, to keep track of ports (by id), 
    // but they bother json now, so we do...
    $base_out[] = $record;
}

$json = json_encode($base_out);

echo $json;

Haven't had the time to test or think twice about it, but again, I hope it conveys the idea...

Answer 2

With thanks to @maraspin, I have got my below code:

function merchantWithProducts($id)
    {
        if (
            !empty($id)
        ) {

            //select all query
            $query = "SELECT
                     m.id as 'mMerchantID', m.name as 'merchantName', m.mobile, m.address, m.city, m.province,
                     p.id as 'ProductID', p.merchantId as 'pMerchantID', p.category, p.productName, p.description, p.price, p.image, p.ratingCount 
                FROM " . $this->table_name . " m 
                JOIN by_product p 
                ON m.id = p.merchantId 
                WHERE m.id = :id 
                GROUP BY m.id";

            // prepare query statement
            $stmt = $this->conn->prepare($query);

            // sanitize
            //  $this->id = htmlspecialchars(strip_tags($this->id));

            // bind values
            $stmt->bindParam(":id", $this->id);

            try {
                $success = $stmt->execute();

                if ($success === true) {

                    $results = $stmt->fetchAll();
                    
                    $this->resultToEncode = array();

                    foreach ($results as $row) {
                       
                        $objItemArray = array(
                            "merchantID" => $row->mMerchantID,
                            "merchantName" => $row->merchantName,
                            "mobile" => $row->mobile,
                            "address" => $row->address,
                            "city" => $row->city,
                            "province" => $row->province, 
                            "product" => array(
                                "productID" => $row->ProductID,
                                "pMerchantID" => $row->pMerchantID,
                                "category" => $row->category,
                                "productName" => $row->productName,
                                "description" => $row->description,
                                "price" => $row->price,
                                "image" => $this->baseUrl . 'imagesProducts/' . $row->image,
                                "ratingCount" => $row->ratingCount
                            )
                        );

                        
                        array_push($this->resultToEncode, $objItemArray);
                    }

                    http_response_code(200);
                    $httpStatusCode = '200 OK';
                    $pass = true;

                    // return json_encode($resultToEncode);
                } else {
                    http_response_code(204);
                    $httpStatusCode = '204 No Content';
                    $pass = false;
                    $this->resultToEncode = 'No Record Found';
                }
            } catch (PDOException $pdoEx) {
                http_response_code(500); // internal server error.
                $httpStatusCode = '500 Internal Server Error';
                $pass = false;
                $this->resultToEncode = $pdoEx->getCode();
            } catch (Exception $ex) {
                // return $ex->getMessage();
                http_response_code(404); // 404 Not Found.
                $httpStatusCode = '404 Not Found';
                $pass = false;
                $this->resultToEncode = $ex->getMessage();
            }
        } else {
            http_response_code(400);
            $httpStatusCode = '400 bad request';
            $pass = false;
            $this->resultToEncode = 'User id not specified';
        }
        echo json_encode(array('passed' => $pass, 'Response' => $httpStatusCode, 'result' => $this->resultToEncode));
    }