对将输出类似于此
的JSON格式进行编码的逻辑方法是什么
{
"Student":{
"studentId":"11-13555",
"Orders":[
{
"transactionId":"20140310-3241-2135",
"Transactions":[
{
"dateOrdered":"2014-07-07 23:21:56",
"productId":12,
"quantity":3
},
{
"dateOrdered":"2014-07-07 23:22:26",
"productId":8,
"quantity":1
}
]
},
{
"transactionId":"20140310-1541-2134",
"Transactions":[
{
"dateOrdered":"2014-07-07 23:23:36",
"productId":12,
"quantity":1
}
]
}
]
}
}
鉴于此表
tblOrders
+==========================================================================================+
| id | transactionId | dateOrdered | studentId | quantity | productId | .... |
|====+=====================================================================================|
| 1 | 20140310-3241-2135 | 2014-07-07 23:21:56 | 11-13555 | 3 | 12 | |
+----+---------------------+---------------------+-----------+----------+-----------+------+
| 2 | 20140310-3241-2135 | 2014-07-07 23:22:26 | 11-13555 | 1 | 8 | |
+----+---------------------+---------------------+-----------+----------+-----------+------+
| 3 | 20140310-1541-2134 | 2014-07-07 23:23:36 | 11-13555 | 1 | 12 | |
+----+---------------------+---------------------+-----------+----------+-----------+------+
我无法想象如何使用此代码对此进行编码：
$result = $conn->query("SELECT * FROM tblOrders WHERE studentId=$studentId GROUP BY transactionId");
if ( $result && $result->num_rows > 0 ) {
$orders = array();
while( $row = $result->fetch_array() ) {
$orders[] = $row;
}
$response["Orders"] = $orders;
//$response["Student"] = "";
$response["status"] = "success";
} else { /* some code... */ }
print json_encode( $response );
因为它给了我一个不一致的“键”，我无法确定它们中的哪一个是我正在寻找的，这是我第一次使用关键字GROUP BY查询数据库。
答案 0 :(得分：0)
皮尤。在吃了一些茶点之后，我已经找到了解决这个问题的一些愚蠢的解决方案。它不是很好，但它“正在工作”并做我想要的。所以我想我会发布我的解决方案：
我把它变成了两个不同的查询。虽然不是那么理想。
如果你们中的一些人有更好的解决方案，请批评这篇文章我很乐意接受它。
$orderList = array();
$result1 = $conn->query("SELECT DISTINCT transactionId FROM tblOrders WHERE studentId = $studentId");
if ($result1 && $result1->num_rows > 0) {
$orders = array();
while ( $row1 = $result1->fetch_array() ) {
$transactionId = $row1["transactionId"];
$result2 = $conn->query(" SELECT"
. " e1.dateOrdered"
. ", e2.name as productName"
. ", e2.price as productPrice"
. ", e1.quantity"
. ", (e1.quantity * e2.price) as totalPrice"
. " FROM tblOrders e1"
. " INNER JOIN tblProducts e2"
. " ON (e1.productId = e2.id)"
. " WHERE transactionId = '$transactionId'"
. " AND studentId = $studentId"
. " ORDER BY dateOrdered");
$transactionList = array();
while( $row2 = $result2->fetch_array() ) {
$transactions["dateOrdered"] = $row2["dateOrdered"];
$transactions["productName"] = $row2["productName"];
$transactions["productPrice"] = $row2["productPrice"];
$transactions["quantity"] = $row2["quantity"];
$transactions["totalPrice"] = $row2["totalPrice"];
$transactionList[] = $transactions;
}
$orders["transactiondId"] = $transactionId;
$orders["Transactions"] = $transactionList;
$orderList[] = $orders;
}
$student["Orders"] = $orderList;
$response["status"] = "success";
$response["Student"] = $student;
} else {
$response["status"] = "failure";
$response["message"] = "No order history";
}
print json_encode( $response );
{
"status":"success",
"Student":{
"Orders":[
{
"transactiondId":"20141028-9364-2677-9324",
"Transactions":[
{
"dateOrdered":"2014-10-28 01:25:55",
"productName":"Polo",
"productPrice":"400",
"quantity":"2",
"totalPrice":"800"
},
{
"dateOrdered":"2014-10-28 01:25:55",
"productName":"Polo",
"productPrice":"400",
"quantity":"1",
"totalPrice":"400"
}
]
},
{
"transactiondId":"20141028-2272-1336-5641",
"Transactions":[
{
"dateOrdered":"2014-10-28 00:13:17",
"productName":"Polo",
"productPrice":"400",
"quantity":"2",
"totalPrice":"800"
}
]
},
{
"transactiondId":"20141027-9409-8121-9023",
"Transactions":[
{
"dateOrdered":"2014-10-27 23:45:22",
"productName":"Polo",
"productPrice":"400",
"quantity":"12",
"totalPrice":"4800"
}
]
},
{
"transactiondId":"20141027-3100-8787-4934",
"Transactions":[
{
"dateOrdered":"2014-10-27 23:21:56",
"productName":"Polo",
"productPrice":"400",
"quantity":"2",
"totalPrice":"800"
}
]
},
{
"transactiondId":"20141027-6525-9465-5526",
"Transactions":[
{
"dateOrdered":"2014-10-27 23:16:13",
"productName":"CLUB SHIRT",
"productPrice":"200",
"quantity":"4",
"totalPrice":"800"
},
{
"dateOrdered":"2014-10-27 23:16:13",
"productName":"Polo",
"productPrice":"400",
"quantity":"10",
"totalPrice":"4000"
},
{
"dateOrdered":"2014-10-27 23:16:13",
"productName":"Polo",
"productPrice":"400",
"quantity":"6",
"totalPrice":"2400"
},
{
"dateOrdered":"2014-10-27 23:16:13",
"productName":"Polo",
"productPrice":"400",
"quantity":"2",
"totalPrice":"800"
},
{
"dateOrdered":"2014-10-27 23:16:13",
"productName":"CLUB SHIRT",
"productPrice":"200",
"quantity":"12",
"totalPrice":"2400"
},
{
"dateOrdered":"2014-10-27 23:16:13",
"productName":"CLUB SHIRT",
"productPrice":"200",
"quantity":"8",
"totalPrice":"1600"
}
]
}
]
}
}
我已经删除了那些“不那么有用”的字段，并在你注意到的情况下提出必要的字段。