php - 使用 PDO 从 MySQL 获取用户信息时出错

Question

我为我正在从事的一个项目设计了一个授权系统。我能够从数据库中检索用户 ID，但是，我现在正在尝试获取该用户的用户名和电子邮件。 顺便说一句，我对 PHP 还很陌生。

我收到此错误:

SQLSTATE[HY093]: Invalid parameter number: parameter was not defined

我很困惑，因为

$stmt->execute() 

但是工作得很好

$stmt2->execute()

失败了。我确信问题很简单，但我无法弄清楚。这是用于获取信息的 PHP 代码。

$stmt = $dbh->prepare("SELECT nuewavedb_user_id, nuewavedb_username, nuewavedb_password FROM nuewavedb_users 
                WHERE nuewavedb_username = :nuewavedb_username AND nuewavedb_password = :nuewavedb_password");

    $stmt2 = $dbh->prepare("SELECT nuewavedb_fullname, nuewavedb_email FROM nuewavedb_users 
                WHERE nuewavedb_username = :nuewavedb_username AND nuewavedb_password = :nuewavedb_password");

    /*** bind the parameters ***/
    $stmt->bindParam(':nuewavedb_username', $nuewavedb_username, PDO::PARAM_STR);
    $stmt->bindParam(':nuewavedb_password', $nuewavedb_password, PDO::PARAM_STR, 40);

    $stmt2->bindParam(':nuewavedb_fullname', $nuewavedb_fullname, PDO::PARAM_STR);
    $stmt2->bindParam(':nuewavedb_email', $nuewavedb_email, PDO::PARAM_STR);

    /*** execute the prepared statement ***/
    $stmt->execute();
    $stmt2->execute();

    /*** check for a result ***/
    $user_id = $stmt->fetchColumn();

    $nuewavedb_fullname = $stmt2->fetchColumn();
    $nuewavedb_email = $stmt2->fetchColumn(1);

预先感谢您的帮助!

Answer 1

您应该以某种方式组合此查询，特别是如果它是同一个表，则无需读取两次

$stmt = $dbh->prepare("SELECT  
                               nuewavedb_user_id
                              ,nuewavedb_username
                              ,nuewavedb_password
                              ,nuewavedb_fullname
                              ,nuewavedb_email  
                       FROM nuewavedb_users 
                       WHERE nuewavedb_username = :nuewavedb_username AND
                             nuewavedb_password = :nuewavedb_password"
        );

然后正确执行并获取:

/*** bind the parameters ***/
$stmt->bindParam(':nuewavedb_username', $nuewavedb_username, PDO::PARAM_STR);
$stmt->bindParam(':nuewavedb_password', $nuewavedb_password, PDO::PARAM_STR, 40);

/*** execute the prepared statement ***/
$stmt->execute();

/*** fetch **/
$row = $stmt->fetch(PDO::FETCH_ASSOC);

$nuewavedb_fullname = $row['nuewavedb_fullname'];
$nuewavedb_email = $row['nuewavedb_email'];