FIX - check for data in SQL result

Author: blondak

include/classes/worker.class.php

@@ -98,7 +98,7 @@ public function getAllIdleWorkers($interval=600) {
    **/
   public function getWorker($id, $interval=600) {
     $this->debug->append("STA " . __METHOD__, 4);
-    $stmt = $this->mysqli->prepare("
+    $stmt = $this->mysqli->prepare($q ="
       SELECT id, username, password, monitor,
         (
           SELECT COUNT(id) FROM " . $this->share->getTableName() . " WHERE our_result = 'Y' AND username = w.username AND time > DATE_SUB(now(), INTERVAL ? SECOND)
@@ -124,8 +124,7 @@ public function getWorker($id, $interval=600) {
          ) AS shares
        FROM $this->table AS w
        WHERE id = ?");
-    if ($this->checkStmt($stmt) && $stmt->bind_param('iiiii', $interval, $interval, $interval, $interval, $id) && $stmt->execute() && ($result = $stmt->get_result())) {
-      $row = $result->fetch_assoc();
+    if ($this->checkStmt($stmt) && $stmt->bind_param('iiiii', $interval, $interval, $interval, $interval, $id) && $stmt->execute() && ($result = $stmt->get_result()) && ($row = $result->fetch_assoc())) {
       $row['hashrate'] = round($this->coin->calcHashrate($row['shares'], $interval), 2);
       if ($row['count_all'] > 0) {
         $row['difficulty'] = round($row['shares'] / $row['count_all'], 2);