Databases may be housed in an outside server to help boost performance. However, this may compromise PCI compliance. 

Frequent Backups

Your database data is your most dynamic and most valuable data. You should install a backup script that is activated by a crontab script at least nightly. 

Naming Convention

Establish naming conventions that are easy to understand and to organize your databases. Even if you anticipate only ever using a single database, chances are the need will arise for a second database during a future upgrade or feature enhancement.