试图从mysql获取数据但导致找不到

Question

Been trying for hours to get data from mysql into my site but i cant figure out what im doing wrong...

Notice: Undefined index: subcatid in C:\xampp\htdocs\website\products.php on line 17

<?php
    $url=$_SERVER['REQUEST_SCHEME']."://".$_SERVER['HTTP_HOST']."/eshopmgk/";

    require_once("connection.php");
    $sql1="select * from prointa where id=".$_GET['catid'];

    mysqli_query($con,'set names "utf8"');

    $recordset=mysqli_query($con,$sql1);    

    $sqla="select * from proionta
            inner join subcatigories on proionta.subcatigories_id=subcatigories.subcatigories_id 
            where subcatigories.subcatigories_alias like  '".$_GET['subcatid']."'";
    $recordsetcannon=mysqli_query($con,$sqla);
?>

.

<div class="col100  products-home-items">
                <?php while($recordcannon=mysqli_fetch_assoc($recordsetcannon)){?>
                    <div class="col25 products-home-item">
                        <div class="col100 items-img">
                            <img width="55%" src="<?=$url?><?=$recordcannon['photos']?>" />
                        </div>
                        <div class="col100 items-title">
                            <a href="#">
                                <p>Φακός</p>
                            </a>
                        </div>
                        <div class="col100 items-category">
                            <a href="<?=$url?>/<?=$_GET['catid']?>/<?=$_GET['subcatid']?>/<?=$recordcannon['proionta_alias']?>"><h3><?=$recordcannon['proionta_name']?></h3></a>                            
                        </div>
                        <div class="col100">                            
                            <div class="col100">
                                <p class="items-price text-center"><?=$recordcannon['proionta_timi']?>&euro;</p>
                            </div>