Question

我的一段php网页代码的sql语句死活出不来，求大神帮助

<form name="zwj_form1" method="post" action="index.php">
<input id="zwj_save" type="submit" value="0-200" />
<input id="text" name="zwj_text_bt" type="text" style="display:none" value="jiage>=0 and jiage < 200"/>
</form>
<?php
连接数据库语句省略
$zwj_tijiao_jiaqian=$_POST["zwj_text_bt"];
$result=mysql_query("select * from zwj_spb where jiage>=0"."$zwj_tijiao_jiaqian"."order by jiage desc;",$conn);
$rows=mysql_num_rows($result);
echo $rows;
?>
报这个错 Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource inC:\wamp\www\xiangmu\index.phpon line144

如果把order by jiage desc这个去掉就对了，求大神指教！！

Answer 1

SQL语句错误。

$result=mysql_query("select * from zwj_spb where jiage>=0"."$zwj_tijiao_jiaqian"."order by jiage desc;",$conn);

其中变量部分$zwj_tijiao_jiaqian='jiage>0 and jiage<200';

那么替换后你的SQL语句是：

select * from zwj_spb where jiage>=0 jiage>0 and jiage<200 order by jiage desc

是不是有问题了？

正确的语法是：

$result=mysql_query("select * from zwj_spb where  {$zwj_tiaojian_jiaqian}  order by jiage desc",$conn);

Answer 2

$result=mysql_query('select * from `zwj_spb` where `jiage` >= 0' . $zwj_tijiao_jiaqian . ' order by jiage desc',$conn);

Answer 3

$result=mysql_query("select * from zwj_spb where jiage>=0"."$zwj_tijiao_jiaqian"."order by jiage desc;",$conn);
//改为：
$result=mysql_query("select * from zwj_spb where jiage>=0 ${zwj_tijiao_jiaqian} order by jiage desc;",$conn);

问题在于你没留空格，其实以后有这样的问题你直接echo它出来就知道问题在哪里