php - 警告：mysqli_stmt::bind_param() [mysqli-stmt.bind-param]：变量数与准备中的参数数不匹配

Question

我不知道为什么我会收到这个错误我认为我有足够的定义参数？！有什么帮助吗？

if ($insert_stmt = $mysqli->prepare("INSERT INTO members (username, email, password, salt, privilegio) VALUES ('".$username."','".$email."','".$password."','".$salt."','".$privilegio."')")) {    
   $insert_stmt->bind_param('sssss', $username, $email, $password, $random_salt, $privilegio); 
   // Execute the prepared query.
   $insert_stmt->execute();
}

Answer 1

应该

if ($insert_stmt = $mysqli->prepare("INSERT INTO members (username, email, password, salt, privilegio) VALUES (?,?,?,?,?)") {    
   $insert_stmt->bind_param('sssss', $username, $email, $password, $random_salt, $privilegio); 
   // Execute the prepared query.
   $insert_stmt->execute();
}