Yuya Hoshino

How it works:
<ol>
<li>
Click ‘Tools > Clone Test DB’.
</li>
<li>
Enter the ‘Test site address’.
</li>
<li>
Select ‘Test database name’.
</li>
<li>
Click ‘Create a clone site’.
</li>
</ol>
<ul>
<li>To view the test site, you will need to transfer files.</li>
<li>Sorry, multi-site is not supported.</li>
</ul>

Clone Test DB

It's a five star plugin just because it works as advertised, and it's easy to use it even though it has it's limitations, and you have to take a couple if (easy) steps.

1. Before cloning the database, edit the target folder's wp-config.php file, and change the database name to the target one (new installation's database). This is the code define( 'DB_NAME', "YOUR_DATABASE_NSME_HERE" );

2. After you clone the database, and if the cloned site is displaying a 404 (page not found) on the posts, pages, cpt, then log in to the backsite, and flash (update) the permalinks, this will solve the 404 errors.

Ok now the limitation: There is only one, and it is the fact that both websites HAVE to be on the same server, you cannot have a localhost -> live situation or vice versa for example, I hope the ability to log in into external databases will be added soon.



It's getting the job done.

Duplicate the table in another database and optimize it as a test site.

postpostmodern

Warning! In developent, not ready for production use. Should be considered alpha at best. 
Tested with WordPress MU 2.9.2 – WordPress 3.1.3 More testing to come. 
Requires PHP 5, as it should.

Clone Test DB vs back data ass up