Php Mysqli准备状态每次都失败

Mysqli prepare语句每次尝试都失败。我试了很多东西，但都不管用。我的密码是：

<?php
include_once 'config.php';
class Database {
function insertImage($title,$desc,$thumbnail_path,$image_path, $uploaded_by){
    $link = mysqli_connect('DB_SERVER', 'DB_USER', 'DB_PASSWORD', 'DB_NAME');

    /* check connection */
    if (!$link) {
        printf("Connect failed: %s\n", mysqli_connect_error());
        exit();
    }
    else{
        $query = "INSERT INTO photos (title, description, thumbnail,image,uploaded_by) VALUES(?, ?, ?, ?, ?)";
        $stmt = mysqli_prepare($link,$query);
        if(!$stmt){
            die("NO statement");
        }
        else
        {
            mysqli_stmt_bind_param($stmt,'sssss',$title,$desc,$thumbnail_path,$image_path,$uploaded_by);
            mysqli_stmt_execute($stmt);
            mysqli_stmt_close($stmt);

        }
        mysqli_close($link);

    }

}

请告诉我哪里出了问题。

---

谢谢。

您没有正确使用课堂。我建议你找一本关于面向对象编程的教程，这样你就会明白了。下面是用基本OO格式重写的类

<?php
include_once 'config.php';
class Database {
    private $conn;//the class property holding your mysqli database object
    function __construct(){
        $this->conn = mysqli_connect('DB_SERVER', 'DB_USER', 'DB_PASSWORD', 'DB_NAME');//construct your $mysqli object.
    }
    public function insertImage($title,$desc,$thumbnail_path,$image_path, $uploaded_by){
        try{
            $query = $this->conn->query("START TRANSACTION;");//start the transaction
            $stmt = $this->conn->prepare("INSERT INTO photos (title, description, thumbnail,image,uploaded_by) VALUES(?, ?, ?, ?, ?);");//OO prepared statement
            $stmt->bind_param('sssss',$title,$desc,$thumbnail_path,$image_path,$uploaded_by);//bind params 
            if(!$stmt->execute()){ //if statement doesn't execute
                throw new Exception('problem with query');//throw execption, the statement failed to execute.
            }else{
                $stmt->close();//close the statement
                $query = $this->conn->query("COMMIT;");//commit the transaction
            }
        catch(Exception $e){
            $query = $this->conn->query("ROLLBACK;");//roll the database back removing any partially commited data.
            return $e->getMessage();
        }

    }
}

---

你犯了什么错误？没有陈述，没有陈述；执行。您确定mysqli_bind_参数中的参数类型都正确吗？请检查您的数据库中是否有“按”字段上载的\u。它闻起来像整数，你在传递字符串。我们可以看看photos表的结构和数据类型吗？你能试试这个吗：如果mysqli_connect_errno{echo无法连接到MySQL:.mysqli_connect_error；}//要检查链接是否已设置，已经检查了连接。我不会为此使用事务。当ACID属性在银行系统中非常重要时，使用事务。否则，对我来说，这似乎是一种过激行为。@Luka如果数据库中有带有默认值的列，它将允许部分数据插入。很明显，您在某个地方读到了这一点，并将其作为个人资料，但相信我，ACID对于用于多种用途的应用程序数据至关重要，而不仅仅是银行系统。我指的是银行系统只是一个示例，而不是交易的专用应用程序。在数据库中允许使用默认值在这里没有多大区别。如果允许使用默认值，则事务不会阻止插入此类记录。

<?php
include_once 'config.php';
class Database {
    private $conn;//the class property holding your mysqli database object
    function __construct(){
        $this->conn = mysqli_connect('DB_SERVER', 'DB_USER', 'DB_PASSWORD', 'DB_NAME');//construct your $mysqli object.
    }
    public function insertImage($title,$desc,$thumbnail_path,$image_path, $uploaded_by){
        try{
            $query = $this->conn->query("START TRANSACTION;");//start the transaction
            $stmt = $this->conn->prepare("INSERT INTO photos (title, description, thumbnail,image,uploaded_by) VALUES(?, ?, ?, ?, ?);");//OO prepared statement
            $stmt->bind_param('sssss',$title,$desc,$thumbnail_path,$image_path,$uploaded_by);//bind params 
            if(!$stmt->execute()){ //if statement doesn't execute
                throw new Exception('problem with query');//throw execption, the statement failed to execute.
            }else{
                $stmt->close();//close the statement
                $query = $this->conn->query("COMMIT;");//commit the transaction
            }
        catch(Exception $e){
            $query = $this->conn->query("ROLLBACK;");//roll the database back removing any partially commited data.
            return $e->getMessage();
        }

    }
}