Yes. If your environment is quite bigger. Definitely go for SQL or Oracle on a sepearte server and create ODBC connections from vCenter Server.
It is always nice to have VC and its database on different servers and you should perform SQL backups every day by running schedules. We have run in to some issues. So, DBA should be required to manage these considering your environment is quite bigger. There are VMware articles out there on how to install and configure this(both SQL and Oracle).