Database design help needed

I am a large social networking site, say mynetwork.com. It will have a lot of features like albums, forums, jobs board and so on (Php + MySQL + Yii)

Now, the users of this site will be able to create networks for their own community which开发者_Python百科 can be accessed by community-1.mynetwork.com or community-2.mynetwork.com etc.

So, I am not sure whats the best way to design the database. One way, I can come up with is to have a unique Id for each network and have a network_Id field in each table.

Is there any better way?

One way, I can come up with is to have a unique Id for each network and have a network_Id field in each table.

Isn't community-1.mynetwork.com already unique?

The process for developing a logical data model is the same whether you're designing a large social networking site or an accounting application, isn't it?

"Have a network_Id field in each table" is an idea. It isn't a design.