I'm not familiar with those libraries, but a quick look gives me the impression that Bridge and Process are used together to make system calls over serial connection on the host system. Based on that..
First, looking at Arduino Process Tutorial Process.begin() should call the process that you want to call. Maybe something like this:
p.begin("curl"); // Assuming you have curl installed on your host system
Second, your PHP script is broken.
/ check connection
^ That comment is missing a second slash /
You should definitely get the PHP/MySQL part working standalone before attempting to integrate Arduino in the process. I'm a bit doubtful that $argv gets populated unless you're running the script from command line. If you're making a GET HTTP request (as you would with curl) you might wanna try instead
$temperature = $_GET['temperature'];
If the above works as a workaround, you should get an entry into your MySQL table if you visit the URL below with your browser.
In any case, get the PHP script working first in your browser. One step at a time.