Joonla on sub domain

The Dreamhost Wiki was nice enough to point out that building a Joomla site on a subdomain was probably a good idea, but it didn't mention how to make it the live site.
Is it as easy as pointing the domain to the subdomain directory? If so, how do I do that?
Will this affect my ability to connect to the MySQL database I use to store information I collect on the current web site?
Thanks,
Matt

There isn't a whole lot that is likely to trip you up. Basically you either do the one-click install to the subdomain, or extract a downloaded archive as usual. Then you'll get routed to the install directory as always when you first visit the site.

Most everything about the install location will be automatically entered, but just insure that you're using the subdomain whenever asked for the site url.

You'll be able to connect to MySQL with the typical database credentials. Just make sure you have a database for the subdomain seperate from any other Joomla installs you might have previously used. I know there is support for multi-site stuff on a single database, but I avoid that for the most part.

Either I don't understand you or I miscommunicated in my first post. Probably the latter.
I already have Joomla! installed in a subdomain, and this site is just about ready to go live. I need to replace the existing site with this Joomla! site.
Can I point my primary domain to the directory with the subdomain? Is that the correct way to do it?
Thanks again,
Matt

Mirror it. It's a kludge, but it's the next best thing to re-installing it as the main domain.
http://wiki.dreamhost.com/Mirror_Domain

-Scott

It's cake. Robert wrote some easy-to-follow instructions in this thread