I have a classifieds website.

In the main page (index) I have several form fields which the user may or may not fill in, in order to specify a detailed search of classifieds.

Ex:

   Category: Cars
   Price from: 3000
   Price to:   10000
   Color: Red
   Area: California

The forms' action is set to a php page:

   <form action='query_sql.php' method='post'>

In query_sql.php I fetch the variables like this:

   category=$_POST['category'];
   etc etc...

Then query MySql:

   $query="SELECT........WHERE category='$category' etc etc....
   $results = mysql_query($query);

Then I simply display the results of the query to the user by creating a table which is filled in dynamically depending on the results set.

However, according to an answer by Col. Shrapnel in my previous Q I shouldn't use POST here: http://stackoverflow.com/questions/3004754/how-to-hide-url-from-users-when-submitting-this-form

The reason I use post is simply to hide the "one-page-word-document" long URL in the browsers adress bar.

I am very confused, is it okay to use POST or not?

It is working fine both when I use GET or POST now... And it is already on a production server...

Btw, in the linked question, I wasn't referring to make URL invisible (or hide it) I just wanted it too look better (which I have accomplished with mod_rewrite).

UPDATE:

If I use GET, then how should I make the url better looking (beautiful)? Check this previous Q out:

http://stackoverflow.com/questions/3000524/how-to-make-this-very-long-url-appear-short