$pull单数组元素

Question

我希望能够删除服务和收费的数组元素1。问题是，任何时候其他元素

包含相同的值，则所有元素都将被删除。1-8和10-15。我已经尝试通过指定

方括号中的元素标识符，这也不起作用。

如果没有重复的值，下面的代码可以很好地工作。我可以毫无问题地删除1和9。

$forward = $_POST['id'];
$conn = new Mongo('localhost');
$db = $conn->pianos;
$collection = $db->names;
$criteria = array('_id' => $forward,);


// Find single document by ID Variable 
$obj = $collection->findOne($criteria);


// define variables for Array objects
$service = $obj['service'] [$i];
$charge = $obj['charge'] [$i];

$serv = array('service' => $service, 'charge' => $charge);

$upsert = true; 
        $collection->update($obj, array('$pull' => $serv) ,array("upsert" =>   $upsert));               

PhpMoAdmin提供的文档结构如下所示。

[$_id] => MongoID Object (
  [$id] => 4e3a8a457bfb8b2817000002
)

[fname] => Billy Bob
[lname] => Thornton

[service] => Array (
[0] => Tune 2 pianos
[1] => Tuned
[2] => Tuned
[3] => Tuned
[4] => Tuned
[5] => Tuned
[6] => Tuned
[7] => Tuned
[8] => Tuned
[9] => Called
[10] => Tuned
[11] => Tuned
[12] => Tuned
[13] => Tuned
[14] => Tuned
[15] => Tuned
)
[charged] => Array (
[0] => 100.00
[1] => 50.00
[2] => 50.00
[3] => 50.00
[4] => 50.00
[5] => 50.00
[6] => 50.00
[7] => 50.00
[8] => 50.00
[9] => 0.00
[10] => 50.00
[11] => 50.00
[12] => 50.00
[13] => 50.00
[14] => 50.00
[15] => 50.00
)

Answer 1

MongoDB对此没有修饰符操作。

您可以为所有条目添加服务日期，以便所有条目都变得唯一。此外，从设计的角度来看，最好将包含服务名称、数据和费用(以及稍后添加的内容)的子文档存储在数组中。

对于当前的“模式”，您唯一能做的就是检索整个文档，在客户端修复它，然后将其写回。这将不是原子的，因此请确保只有一个用户可以在特定时间修改文档。