Database separation - MySQL

Question

I have a main MySQL db set up, and a class to handle the queries to it. It runs real nice. I am building a custom advertising system on my site and I'm wondering if there is any benefit to creating a separate database all together to handle that system?

Is there any pitfalls to doing it either way?

Option #1 - one DB for main website function, one DB for advertising system

Option #2 - one DB for both main website function and advertising system

Answer 1

Well, you need a new connection for every Database you use, also you need a new instance of your DB-Class - both costs some (minimal) memory. I personally see no reason why you would need/want to do this. If you just want to separate the two things, maybe you could use a prefix like "adv_" for the advertisement tables.

Edit: another problem could come up if you ever want to combine (e.g. join) data of the two databases - you will have a much easier time if you do not use multiple databases.