sql删除使用内连接超过3个表

Question

我运行这个 sql 语句使用内部连接从数据库中删除，但是我得到了太多错误

错误

致命错误：带有消息的未捕获异常“PDOException” 'SQLSTATE[42000]: 语法错误或访问冲突：1064 你有一个 SQL 语法错误；检查与您对应的手册 MariaDB 服务器版本，用于在 'INNER JOIN 附近使用正确的语法 ipaddress_likes_map ON ipaddress_likes_map.postat = blog_post.BID INN' 在 C:\xampp\htdocs\codejail.net_inc\dbcontroller.php:57 的第 3 行 堆栈跟踪：#0 C:\xampp\htdocs\codejail.net_inc\dbcontroller.php(57)： PDOStatement->execute() #1 C:\xampp\htdocs\codejail.net\user\deleteaccount.php(88)： DBController->execute() #2 {main} 抛出 C:\xampp\htdocs\codejail.net_inc\dbcontroller.php 第 57 行

这是我的代码

<?php
   if(isset($_POST['delete'])){
     $pass = $_POST['pasyske'];
     $userkey = $_POST['username'];
     $db_delete = new DBController();
     $db_delete->prepare("DELETE
FROM blog_post
INNER JOIN ipaddress_likes_map ON ipaddress_likes_map.postat = blog_post.BID
INNER JOIN flagpost ON flagpost.postId = blog_post.BID
INNER JOIN postviewmap ON postviewmap.viewpostId = blog_post.BID
INNER JOIN replys ON replys.rid = blog_post.BID
INNER JOIN votepoint_map ON votepoint_map.postlike_id = blog_post.BID
WHERE blog_post.UserName = :alluserpost");
     $db_delete->bind(":alluserpost", $userkey);
     //$db_delete->bind(":password", $encrypt_password);
     $db_delete->execute();
     $pdeleted = $db_delete->getAll(); 
     $db_delete->free();

    if($pdeleted){
        print_r($pdeleted);
    }

   }?>

我确定我的数据库控制器没问题，因为当我运行单个删除语句时它工作得很好

Answer 1

给每个表一个别名，并在单词DELETE 之后引用它。另外，请使用LEFT JOIN 而不是INNER JOIN，因为我猜如果某些联接表没有匹配的行，您仍然希望删除工作事件。

db_delete->prepare("DELETE bp, i, f, p, r, v
FROM blog_post AS bp
LEFT JOIN ipaddress_likes_map AS i ON i.postat = bp.BID
LEFT JOIN flagpost AS f ON f.postId = bp.BID
LEFT JOIN postviewmap AS p ON p.viewpostId = bp.BID
LEFT JOIN replys AS r ON r.rid = bp.BID
LEFT JOIN votepoint_map AS v ON v.postlike_id = bp.BID
WHERE bp.UserName = :alluserpost");

Answer 2

在 DELETE 之后，您应该告诉从哪个表中删除行。试试这个查询：

$db_delete->prepare("DELETE blog_post 
FROM blog_post
INNER JOIN ipaddress_likes_map ON ipaddress_likes_map.postat = blog_post.BID
INNER JOIN flagpost ON flagpost.postId = blog_post.BID
INNER JOIN postviewmap ON postviewmap.viewpostId = blog_post.BID
INNER JOIN replys ON replys.rid = blog_post.BID
INNER JOIN votepoint_map ON votepoint_map.postlike_id = blog_post.BID
WHERE blog_post.UserName = :alluserpost");