插入 - 绑定变量的数量与准备好的语句中的字段数量不匹配

I'm getting:

Warning: mysqli_stmt::bind_result(): Number of bind variables doesn't match number of fields in prepared statement in E:XAMPPhtdocsaccountlibegister.php on line 73

When I use this code:

if($stmt = $conn -> prepare("INSERT INTO login(user, pass) VALUES(?, ?)")) {

  /* Bind parameters s - string, b - blob, i - int, etc */
  $stmt -> bind_param("ss", $user, $pw);

  /* Execute it */
  $stmt -> execute();

  /* Bind results */
  $stmt -> bind_result($user, $pw);

  /* Close statement */
  $stmt -> close();
  $userId = $conn->insert_id;
} 

I can't understand, why this happens every time, what is wrong in my code snippet?

解决方案

You are attempting to bind_result on a statement that is not returning any results.

Remove this line. $stmt -> bind_result($user, $pw);