I am controlling a recognised site that is presently along the way to be upgraded (completely changed anew), but I am worried that I'll lose my Google indexing (that's, you will see lots of pages in Google's index which will not exist for the reason that place anymore).
The final time I upgraded a (different) site, someone explained I ought to did something to ensure that my Search engine optimization is not negatively affected. The issue is, I can not remember what that something was.
Update for many clarification: Essentially I am searching for a way to map that old pathways to they. For instance:
- User looks for "awesome page"
- Google returns
mysite.com/old_awesome_page.php, user clicks it.
- My website takes these to
So when Google will get around to moving the website again...
- Google crawls my website, refreshing the present indexes.
- My website informs Google the page has gone to live in
There will not be considered a simple 1:1 mapping like this, it will be a lot more like
(old) index.php?page=awesome --> (new) index.php/pages/awesome, and so i can't just replace the items in the present files with redirects.
I am using PHP on Apache
301 redirect all of your old (gone) pages to they.
Edit: Here's a link to help. It features a couple of links with other places too.
You have to put some rewrite rules within an .htaccess file.
You'll find plenty of reliable information here. It's for Apache 1.3, however it works best for Apache 2, too.
From it, an example for redirecting to files which have moved sites:
RewriteEngine on RewriteRule ^/~(.+) http://newserver/~$1 [R,L]
- Switch on the rewrite engine.
- For something that begins with /~, then a number of of "anything", rewrite it to http://newserver/~ then that "anything".
- The [L] implies that the spinning should stop following this rule.
You will find additional directives which you can use to create a  redirect
You could do this:
RewriteEngine on RewriteRule old_page.php new_page.php [L]
But you'd need to have a rule for each page. To avert this, I'd take a look at using Regular Expressions, as with the very first example.
You are able to tune Google's look at your website, and most likely inform its changes, from inside Google Webmaster Tools. I believe you need to develop a sitemap of the current site, and also have it verified once the site changes.