As RL has noted there are a few ways to accomplish this but in the end it comes down to what you have in your database and what you need in your merged database.
Points are easy, you could export them all to a csv and then re-import to the new database or import from drawing as RL noted.
The survey figures get more complicated. If they are figures I assume they were created through an import event into the current database? if so, you could simply import all of the survey events from one database to another. There are some inherent issues in doing this as you will lose any figure edits you made, if any.
If you just need the linework, points and a surface i would simply re-associate a drawing from 1 database to the other one. This would enable you to data shortcut the surface easily. It really comes down to what you have and what you need.
We don't merge databases often, if ever, but certainly share data between projects and drawings on a daily basis using a variety of methods and procedures that meet our and our clients needs.