So ändern Sie Datenbankinhalte in PHP

<?php
    header("Content-Type:text/html;charset=utf8"); 
    header("Access-Control-Allow-Origin: *"); //解决跨域
    header(&#39;Access-Control-Allow-Methods:POST&#39;);// 响应类型  
    header(&#39;Access-Control-Allow-Headers:*&#39;); // 响应头设置 
    $link=mysql_connect("localhost","root","root"); 
    mysql_select_db("business_card", $link); //选择数据库
    mysql_query("SET NAMES utf8");//解决中文乱码问题
    $wx_id = $_POST[&#39;wx_id&#39;];
    $openid = $_POST[&#39;openid&#39;];
    $q = "SELECT * FROM user"; //SQL查询语句 SELECT * FROM 表名
    $rs = mysql_query($q); //获取数据集
    if(!$rs){die("数据库没有数据!");}
//循环读取数据并存入数组对象
    $dlogs;$i=1;
    while($row=mysql_fetch_array($rs))
    {
$result = @mysql_query($strsql);
        if($row["openid"]==$openid){
if($row["collect"]!=""){
$ab =$row["collect"].&#39;,&#39;.$wx_id;
}else{
$ab =$wx_id;
}
//修改数据库字段
mysql_query("UPDATE user SET collect = &#39;$ab&#39;
WHERE openid = &#39;$openid&#39;");
 
    echo urldecode(json_encode($ab));
}
    }
    //以json格式返回html页面
   
    
?>