MySQL standard

The kind of thing you're describing is usually done by a full time four year college engineering major.

I think I would start by making a Google search for "learning mysql" and would follow the many good links that can point you to learning resources.  You will quickly see that this is not a good area to be guessing, especially since you're going to be setting the foundation for your company's applications.  Once you have done that, you might want to go to a nearby college or university and hire someone in the computer science department who is an expert in data base design and administration.  You can make a modest investment now and enjoy a strong foundation for growth or you can spend your career struggling, patching and repairing a botched design.  

I've seen this happen too many times.  As but one example of what can go wrong, consider the rollout of the US healthcare.gov web site.  They spent over half a billion dollars but because they started with flawed underpinnings the site still does not work, and is a huge embarrassment for the administration!

As the great oil-well firefighter Red Adair famously said, "If you think it's expensive to hire a professional, just wait till you hire an amateur!"

thanks!