php提示Warning:mysql_fetch_array() expects的解决方法_PHP
本文实例讲述了php提示Warning mysql_fetch_array() expects的解决方法,分享给大家供大家参考。具体分析如下:
在mysql数据库连接时碰到Warning: mysql_fetch_array() expects ...错误提示,根据我的经验这个是sql返回的query为空了,我们没有加己判断直接使用了.
mysql_fetch_array()函数导致的,下面我们一起来看问题解决方案,我的代码如下:
代码如下:
include("conn.php");
if(!empty($_GET['id'])){
$sql="select * from news where `id`='".$_GET['id']."'";
$query=mysql_query($sql);
$rs = mysql_fetch_array($query);
}
提示错误了: 代码如下:
if(!empty($_GET['id'])){
$sql="select * from news where `id`='".$_GET['id']."'";
$query=mysql_query($sql);
if( mysql_num_rows( $query )
{
$rs = mysql_fetch_array($query);
}
else
{
mysql_error();
}
}
这样就会看到mysql错误信息了,结果是sql语句有问题了,把sql语句进行修改就可以了.
提示:导致这类错误是我们语法不规范了,如果要处理只有对sql进行一条条输出处理或在mysql_query(sql) or die(mysql_error()) 这样来处理,以便更准确的定位错误。
希望本文所述对大家的PHP程序设计有所帮助。

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