如何使用 PHP 正确检查 MongoDB Atlas 数据库中的现有数据。 我总是知道名字已经存在

Question

    $query = ['name' => $name];

    $options = [];
    $queryDriver = new MongoDB\Driver\Query($query, $options);

    $execute = $conn->executeQuery('db.collection', $queryDriver);

    //validation if a user exists
    if (!empty($execute)) {
      $err['name'] = 'this name already exists';
    } else {
      echo 'this name doesnt exist';

I am trying to create a register form but i can't validate if a name already exists.

Answer 1

Your issue is not connected to the database query result. In your code, you have in the first line

    $query = ['name' => $name];

and at the end of the script, you are checking

 if (!empty($query)) {

$query is not empty at this moment (it is ['name' => $name] ). Instead of validating the query result, you are validating the query condition.