Eric Nagel

In step 3, we’re going to actually display the data saved in the database! So far I’ve held your hand along the way, but now I’m just going to point you in the right direction, because there isn’t one way to do this. Merchants handle categories in their datafeeds differently, so you’re going to have to look at what the merchants you’ve chosen to work with are doing, and adjust accordingly.

Looking at my tea example, I wanted pages for Green Tea, White Tea, Black Tea and Oolong Tea. So (in theory, I don’t do it this way) we could make the Green Tea page /browse.php?cCategory=green+tea, and then pull in all the green teas. How do we do that? This is where you have to think.

What I’m doing is the following:

select * from products where MerchantSubcategory like '%green tea%' or MerchantCategory like '%green tea%' order by Name;

That works nicely for my dataset. However, if you were using the Baghaus datafeed, your query may be

select * from products where Name like '%Tylie Malibu%' order by Price desc;

Once you have your data, loop through it & display the products on the page, with a link to the product details page. You can use a list, or a table… whatever you’d like. In the end, you’ll be linking to individual products, like: /item.php?ProductID=466820102

And on item.php, you’ll do a quick lookup and display the product:

$cQuery = "select * from products where ProductID=" . (int)$_GET['ProductID'] . " limit 1";
$oResult = mysql_query($cQuery);
$rsData = mysql_fetch_array($oResult);

<a href="<?= $rsData['Link'] ?>" title="<?= $rsData['Name'] ?>" rel="nofollow"><?= $rsData['Name'] ?></a>

If you look at my tea site, you’ll notice I’m not using links like those in the blog post. Instead, I’m using .htaccess to rewrite the URLs, to make them “pretty”. You can learn about this in my Follow-up on Datafeeds Podcast blog post.

Finally, one problem you’ll be sure to run into is that merchants often have broken images in their datafeeds. This sucks, but there isn’t much you can do about it.

At first, I had a PHP script that made sure the image existed, and if so displayed it and if not, displayed another one. But, that slowed down the page display considerably. So instead, I use a bit of Javascript to replace broken images with a pre-defined image:

<script language="JavaScript" type="text/javascript">
function ImgError(source){
	source.src = "/images/no-image.gif";
	source.onerror = "";
	return true;
}
</script>

Warren Buffett once commented, “I want to give my kids just enough so that they would feel that they could do anything, but not so much that they would feel like doing nothing”.

In this datafeed series, I want to think the same thing. If I give you a finished site, you haven’t learned anything. However, if I give you the framework, and set you in the right direction, the finished product will be something you developed, not something you copied.

If you’ve followed from Step 1, and I know some of you have, you should be well on your way to a finished site. But if you’re waiting for a template to work off of, here it is:

By no means is this a website that you can actually launch, but the framework is there for you to build off of.

As always, if you need help, leave a comment, email me, or find me on Twitter @ericnagel

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