Question

我试图在mysql的一个查询中从多个表中删除。它给了我以下错误：

错误：您的SQL语法有错误;检查与MySQL服务器版本对应的手册，以便在'* FROM posts INNER JOIN fields_data附近使用正确的语法在第1行的posts.post_id = fields_data.post_id W'

<?php
include "connection.php";

$id=@$_GET['pid'];

$ssq="DELETE FROM `posts` INNER JOIN `fields_data` ON posts.post_id =   
fields_data.post_id WHERE posts.post_id= '$id'";
$query=mysqli_query($con,$ssq);
if($query){
 header("location:home.php?del=The post has been deleted successfully");
 }
else{
echo "ERROR:".mysqli_error($con);
}

?>

Answer 1

在DELETE关键字后使用表格名称

$ssq="DELETE `posts` FROM `posts` INNER JOIN `fields_data` ON posts.post_id =   
fields_data.post_id WHERE posts.post_id= '$id'";

使用别名来更好地理解

$ssq="DELETE p FROM `posts` as p INNER JOIN `fields_data` as fd ON p.post_id =   
fd.post_id WHERE p.post_id= '$id'";

修改

如果要删除两个表中的记录，只需在DELETE关键字后指定表名：

$ssq="DELETE `posts`,`fields_data` FROM `posts` INNER JOIN `fields_data` ON posts.post_id = fields_data.post_id WHERE posts.post_id= '$id'";

Answer 2

试试这个..

您经常在SELECT语句中使用INNER JOIN子句从表中选择其他表中具有相应记录的记录。为了更方便，MySQL还允许您使用带有DELETE语句的INNER JOIN子句来删除表中的记录以及其他表中的相应记录，例如，删除满足特定条件的T1和T2表中的记录，您使用以下语句：

DELETE T1, T2
FROM T1
INNER JOIN T2 ON T1.key = T2.key
WHERE condition

您的代码

$ssq="DELETE posts,fields_data FROM `posts` as posts INNER JOIN `fields_data`as fields_data ON posts.post_id =   
fields_data.post_id WHERE posts.post_id= '$id'";

http://www.mysqltutorial.org/mysql-delete-join/

我的删除查询无效

2 个答案: