Mauro Cardarelli wrote a nice “to the point” article on how to recover a site collection from the SQL database backups. You can find his article here: http://blogs.officezealot.com/mauro/archive/2007/12/12/20674.aspx

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You go to your portal this morning and instead of seeing the home page you are greeted with a ’404′ error page. Something is wrong! You look in Central Administration and you notice that your Web Application is there but the site collection is gone. Ouch! Time to recover…

In this scenario, let’s assume that you have NOT been doing site collection backups but you do have SQL backups. You notice that last night’s content database backup is considerably smaller than the night before (yes, you have been saving multiple days of backups). Phew! Your data is all there; we just need to reconnect it. Here’s how:
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