一个简单实现多条件查询的例子
    在我们的网站设计过程中,经常会用到多条件查询,本文的源码是一个二手房屋查询的例子。在本例中,我们要实现能够通过地理位置,物业类型,房屋价格,房屋面积及信息发布日期等多个条件查询到客户所需的资料。以下是实现过程。
查询条件界面(略):
查询文件(search.php)
一、生成查询语句:
<?
$conn
=mysql_connect("localhost","root","");
$db=mysql_select_db("lingyun");
$query="select * from message where tradetype='".$tradetype."'";  //交易类型,如出租,出售
$SQL=$SQL "wuye='" $wuye "'";
if(
$housetype!="不限"){
$query.=" && housetype='".$housetype."'"//房屋类型,如二室一厅,三室二厅
}
if(
$degree!="不限"){
$query.=" && degree='".$degree."'";  //新旧程度
}
if(
$wuye!="不限"){
$query.=" && wuye='".$wuye."'";   //物业类型 如住房,商铺
}
if(
$price2!=""){
switch(
$price1){
case 
"大于":
$query.=" && price>'".$price2."'";   //价格
break;
case 
"等于":
$query.=" && price='".$price2."'";
break;
case 
"小于":
$query.=" && price<'".$price2."'";
break;
 }
}
if(
$area2!=""){
switch(
$area1){
case 
"大于":
$query.=" && area>'".$area2."'";  //面积
break;
case 
"等于":
$query.=" && area='".$area2."'";
break;
case 
"小于":
$query.=" && area<'".$area2."'";
break;
 }
}
switch(
$pubdate){                   //发布日期
case "本星期内":
$query.=" && TO_DAYS(NOW()) - TO_DAYS(date)<=7";
break;
case 
"一个月内":
$query.=" && TO_DAYS(NOW()) - TO_DAYS(date)<=30";
break;
case 
"三个月内":
$query.=" && TO_DAYS(NOW()) - TO_DAYS(date)<=91";
break;
case 
"六个月内":
$query.=" && TO_DAYS(NOW()) - TO_DAYS(date)<=183";
break;
}
if(
$address!=""){
$query.=" &&  address like '%$address%'";  //地址
}
if(!
$page){
$page=1;
}
?>

二、输出查询结果:
<?php
     
if ($page){
     
$page_size=20;
     
$result=mysql_query($query);
     
#$message_count=mysql_result($result,0,"total");
     
$message_count=10;
     
$page_count=ceil($message_count/$page_size);
     
$offset=($page-1)*$page_size;
     
$query=$query." order by date desc limit $offset, $page_size";
     
$result=mysql_query($query);
     if(
$result){
     
$rows=mysql_num_rows($result);
     if(
$rows!=0){
     while(
$myrow=mysql_fetch_array($result)){
     echo 
"<tr>";
     echo 
"<td width='15' height='12'><img src='image/home2.gif' width='14' height='14'></td>";
     echo 
"<td width='540' height='12'>$myrow[id]&nbsp;$myrow[tradetype]&nbsp;$myrow[address]&nbsp;$myrow[wuye]($myrow[housetype])<font style='font-size:9pt'>[$myrow[date]]</font>";
     echo 
"</td>";
     echo 
"<td width='75' height='12'><a href='view_d.php?code=$myrow[code]' target='_blank'>详细内容</a></td>";
     echo 
"</tr>";
         }
       }
     else echo 
"<tr><td><div align='center'><img src='image/sorry.gif'><br><br>没有找到满足你条件的记录</div></td></tr>";
     }

         
$prev_page=$page-1;
         
$next_page=$page+1;
         echo 
"<div align='center'>";
         echo 
"&nbsp;第".$page."/".$page_count."页&nbsp";
         if (
$page<=1){
             echo 
"|第一页|";
            }
         else{
             echo 
"<a href='$PATH_INFO?page=1'>|第一页|</a>";
             }
         echo 
" ";
         if (
$prev_page<1){
             echo 
"|上一页|";
            }
         else{
             echo 
"<a href='$PATH_INFO?page=$prev_page'>|上一页|</a>";
             }
         echo 
" ";
         if (
$next_page>$page_count){
             echo 
"|下一页|";
             }
         else{
             echo 
"<a href='$PATH_INFO?page=$next_page'>|下一页|</a>";
              }
         echo 
" ";
         if (
$page>=$page_count){
             echo 
"|最后一页|";
               }
         else{
             echo 
"<a href='$PATH_INFO?page=$page_count'>|最后一页|</a>";
             }
        echo 
"</div>";
    }
     else{
         echo 
"<p align='center'>现在还没有房屋租赁信息!</p>";
       }
   echo 
"<hr width="100%" size="1">";
  
?>
    </table>