How do I redirect index.php ONLY when there is no query string?

Question

How do I create a rewrite rule that only matches a request with no query string?

http://www.mysite.com/index.php

should remap to:

http://www.mysite.com/

BUT

 http://www.mysite.com/index.php?page=some_page

Should be left alone.

I'm trying this:

RewriteRule ^/index.php$   http://www.mysite.com/ [R=301,L]

...But it's matching anything that starts with /index.php even though I've explicitly ended the pattern with a dollar sign.

UPDATE:

The only rules before this one are:

 RewriteCond %{HTTP_HOST}   ^mysite.com [NC]
 RewriteRule ^/(.*)         http://www.mysite.com/$1 [R=301,L]

The intention is to redirect non www links to the www version.

Answer 1

The [L] flag on the first set of rules here:

RewriteCond %{HTTP_HOST}   ^mysite.com [NC]
RewriteRule ^/(.*)         http://www.mysite.com/$1 [R=301,L]

L means Last -- Apache will stop processing rules for this iteration when it is reached.

Remove the L flag and you should be fine.

Answer 2

RewriteCond ! %{QUERY_STRING} would match requests without a query string.

You can also add the following to turn on logging and debugging of mod_rewrite RewriteLog logs/rewrite_log RewriteLogLevel 3

Be aware that this can slow you site down and fill up your logs so only use it for debugging.

Answer 3

All these rewrites are RegExps which are quite slow. It should be a bit faster if you do it from index.php:

if (!strlen($_SERVER["QUERY_STRING"])) header("Location: /");

Answer 4

Here's the solution I came up with:

RewriteCond %{QUERY_STRING} ^$
RewriteRule ^/index.php$   / [R=301,L]