Php MySQL连接查询似乎有效,但未按预期执行

Php MySQL连接查询似乎有效,但未按预期执行,php,mysql,sql,Php,Mysql,Sql,我对在MySQL中使用连接比较陌生 我有两张桌子: sh_subscriptions => id => user_id => feed_id sh_feeds => id => shop_name => feed_id 我正在尝试从sh_订阅中获取所有字段,其中feed_id对应于sh_feed中的feed_id,对应于$row['shop_name'],而user_id对应于$id['id] 以下是我的尝试

我对在MySQL中使用连接比较陌生

我有两张桌子:

sh_subscriptions
    => id
    => user_id
    => feed_id

sh_feeds
    => id
    => shop_name
    => feed_id
我正在尝试从
sh_订阅
中获取所有字段,其中
feed_id
对应于
sh_feed
中的
feed_id
,对应于
$row['shop_name']
,而
user_id
对应于
$id['id]

以下是我的尝试:

SELECT * FROM sh_subscriptions s
INNER JOIN sh_feeds f ON s.shop_id = f.feed_id
WHERE s.id = '" . $id['id'] . "'
AND f.shop_name = '" . $row['shop_name'] . "'
更新

我现在有以下资料:

while($row = mysqli_fetch_array($query))
{
    echo "<div class='col-md-4'>";
    echo $row['shop_name'] . " ";
    $query = mysqli_query($con, "SELECT * FROM sh_subscriptions s INNER JOIN sh_feeds f ON s.feed_id = f.feed_id WHERE s.user_id = '" . $id['id'] . "' AND f.shop_name = '" . $row['shop_name'] . "'") or die(mysql_error($con));
    echo "</div>";
}
while($row=mysqli\u fetch\u数组($query))
{
回声“;
echo$行['shop_name'];
$query=mysqli_query($con,“从sh_订阅的内部连接中选择*sh_feed f ON s.feed_id=f.feed_id,其中s.user_id='”“$id['id']。”和f.shop_name='”“$row['shop_name'.'”))或die(mysql_错误($con));
回声“;
}
我可以确认数据库字段都存在,并且变量打印正确,但是尽管包含了错误处理程序,但是
div
中没有任何内容被打印出来。

尝试以下操作:

SELECT * FROM sh_subscriptions s
INNER JOIN sh_feeds f ON s.id = f.feed_id
WHERE s.id = '" . $id['id'] . "'
AND f.shop_name = '" . $row['shop_name'] . "'") or die(mysql_error($con));
我想应该是这样

SELECT * FROM sh_subscriptions s
INNER JOIN sh_feeds f ON s.feed_id = f.feed_id
WHERE s.id = '" . $id['id'] . "'
AND f.shop_name = '" . $row['shop_name'] . "';

为什么使用s.shop\u id=f.feed\u id而不是s.feed\u id=f.feed\u id?“没有按预期执行”,如何执行?是否存在
sh_订阅。店铺id
?您不会在列列表中显示它。