public static function getAllSubmissions()
 {
     // Return all of the submissions as an array of Submission objects
     $query = "SELECT Submissions.assignmentNumber, Submissions.submissionFile, \r\n\t   \t\t            Users.userName FROM Submissions LEFT JOIN Users ON Submissions.userId = Users.userId ";
     $submissions = array();
     try {
         $db = Database::getDB();
         $statement = $db->prepare($query);
         $statement->execute();
         $submissions = SubmissionsDB::getSubmissionsArray($statement->fetchAll(PDO::FETCH_ASSOC));
         $statement->closeCursor();
     } catch (PDOException $e) {
         // Not permanent error handling
         echo "<p>Error getting all submissions " . $e->getMessage() . "</p>";
     }
     return $submissions;
 }
 public static function getSubmissionsBy($type = null, $value = null)
 {
     // Returns Submission objects whose $type field has value $value
     $submissionRows = SubmissionsDB::getSubmissionRowSetsBy($type, $value);
     return SubmissionsDB::getSubmissionsArray($submissionRows);
 }