Pass custom var in url

Ok. Anyone see what I did wrong in the code above? I just found it. ? should be an &. Works now.

For future reference, it looks like this is about the simplest way I can think of to pass a variable to a page. Other form post/get or session based methods seem to be more complex.

$wh = $_GET[‘wh’];

beyond it being completely insecure?

My objective is to show content of external database on a wordpress page.

I have created a page template that includes php and an sql query that will query a non wordpress database on the fly. I wish to control the ouput of this page by getting a variable from the url.

For example a url linking to this page may look like this:
https://myblog.com?merchant=xyz

I would then like to grab the “merchant” variable and insert into the sql code on the page template.

I have tried

WHERE merchant = ‘<?php echo $_GET[“$merchant”]; ?>’

without success

Are there any suggestions?

Many thanks in advance

In case it helps anyone else like me with little coding knowledge I achieved my objective by defining the variable using
$q = (isset($_GET[“q”])

where q is the merchant defined in the url

The sql simply included the command WHERE merchant = ‘$q’