If you were previously using the internal Derby database, you will be able just to copy over almost everything from under the database directory which is right under your CA_OM_Web_Viewer directory. Do not copy the RunTimeCacheDB folder. That is generated by the Server in real time and can cause problems if the old one is brought over.
If you were using an external database, you can just use the same one and update the credentials in the config tool. There were no changes to the database structure.