mod_rewrite rule to match first letter

Question

I have urls structured like this http://domain.com/search.php?query=perks
I want to be able to match the first letter of the query "in this case perks" and make a url like this
http://domain.com/p/perks
I would also like it so that if the query starts with a number EX query "1 perk" that it will make a url like this.
domain.com/1/1+perk
Does anyone know how to achieve the matching of the first character of the search to make urls structured like this? Thanks

Answer 1

As the mod_rewrite documentation explains,

If you wish to match against the hostname, port, or query string, use a RewriteCond with the %{HTTP_HOST}, %{SERVER_PORT}, or %{QUERY_STRING} variables respectively.

Therefore, the solution is:

RewriteCond %{QUERY_STRING} (^|&)query=(([^&])[^&]*)
RewriteRule ^/search.php /%3/%2?

By the way, the + decodes to a space character only if it is in a query string. A space in the path portion of a URL should be encoded as %20; a + in the path portion of the URL should generally be interpreted literally.