为什么总是Warning: mysql_fetch_object(): supplied argument is not a valid MySQL resul-PHP Tutorial-php.cn

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为什么总是Warning: mysql_fetch_object(): supplied argument is not a valid MySQL resul

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Jun 23, 2016 pm 02:02 PM

为什么总是

Warning: mysql_fetch_object(): supplied argument is not a valid MySQL result resource in D:\AppServ1\www\forum\index.php on line 46

代码：
               $id = $row["id"];
   $res=mysql_query("select count(*) as total from reply where topic id='$id'");
   $r = mysql_fetch_object($res);
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回复讨论(解决方案)

topic id='$id'" //这里错了吧

怎么改呢？。。。。。

你把SQL语句放到MYSQL里面运行，看有没有结果

最后的$id用连字符拼接吧，别直接写到sql里

表结构和需求都不贴出来，怎么改只有你自己知道。

topic 什么东西

$res = mysql_query("select count(*) as total from reply where id=".$id);

topic是另外一张表

topic是另外一张表那得采用连接查询或者是多表符合查询

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