Question

我收到以下错误：

 Warning: mysqli_stmt_bind_result(): Number of bind variables doesn't match number of fields in prepared statement in  line 48

以下是第48行

mysqli_stmt_bind_result($stmt, $user_email, $user_pass);

以下是代码的更大部分

   // Using mysql_real_escape_string to ensure that the statements are legal SQL statements that can be stored
      $email = mysqli_real_escape_string($con, $_POST['email']);
      $password = mysqli_real_escape_string($con, $_POST['password']);


      /*

        Using Prepared statement to prevent SQL Injection

      */


      //  Create a perepared statement 
     if($stmt = mysqli_prepare($con, "SELECT * from admins WHERE user_email=? AND user_pass=?")) {


        // Bind the paramaters
        mysqli_stmt_bind_param($stmt, "ss", $email, $password);


        // Execute the query
        mysqli_stmt_execute($stmt);


        /*

         Usually we would bind the result to be able to retrieve their given value
         However, in this case we are not interested in retrieving values from the database

        */
           /* fetch value */
        mysqli_stmt_fetch($stmt);


        /* bind result variables */
         mysqli_stmt_bind_result($stmt, $user_email, $user_pass);

         echo $user_email;

连接已正确建立，即使myqsli_prepare查询中没有设置条件，我仍然会检索相同的错误。

非常感谢任何帮助。

Answer 1

选择问题是，您选择的列数超过2列，只在mysqli_stmt_bind_result中绑定2，换句话说，select中的列数必须与mysqli_stmt_bind_result中的变量数相同

要修复，请更改

SELECT * from admins WHERE user_email=? AND user_pass=?

要：

SELECT user_mail, user_pass from admins WHERE user_email=? AND user_pass=?"

警告：mysqli_stmt_bind_result（）：绑定变量数与预准备语句中的字段数不匹配

1 个答案: