How can I "time-stamp" my data without publishing it?
Basically, I want to protect myself upfront against My research work stolen and published as his own by the co-author without my consent


What you need is to convince the research community that this is your work, so that if anyone tries to steal it, then it will be considered professional misconduct, they won't be able to publish their theft, etc.  I'm not convinced copyright law is the right tool for this.  Sure, being able to sue someone for copyright violation could be useful in certain circumstances, but often it won't actually settle the academic issues.  For example, collaboration.  I might claim to have collaborated with you on the research contained in the database, in which case I would be entitled to be a coauthor on academic publications, and you would be considered to be acting unethically if you denied me coauthorship.  There's no way to defend against this using copyright registration, cryptographic time-stamping, etc.  You might be able to prove that you already had a copy of the database in the past, but it's much harder to prove that I didn't somehow contribute to it, except in extreme cases such as having had a copy before I first studied this field.

In practice, people often deal with this difficulty by telling more people.  If you tell just one person about your work, then they can steal it, and it's your word against theirs.  If you tell ten people, then it's much harder for a thief to get away with it, since there are nine other witnesses.  If you tell a hundred, then it becomes really difficult to steal your work.  Unless someone immediately tries hard to steal it, it will become impossible: the community will react by saying "Wait, Quora Feans told all of us about this database last year.  If it was your work, why didn't you say anything back then?"

Whether more publicity is a viable solution depends on your circumstances, but there's a fundamental trade-off here.  Ultimately, academia cares about credit for the ideas and research, not just who owns the copyright.  (If I write a paper about your work, then I own the copyright to my words, but I don't deserve credit for the ideas.)  The more you keep your work secret, the harder it is to prove anything about who deserves the intellectual credit.