Implementing an alternative database for blog.

I have built a client website and they have sent me a backup of their blog that they wish to add to the site. If I import it to the myPHPAdmin database then it essentially deletes the site, of at least leaves it as a blank white page.

Is there a way therefore to add a separate database and import that to a blog page, allowing the client to post to the blog which would add the post to that database and leave the rest of the site intact? Or is the only solution the rebuild the site with the new database?

Thanks in advance.