I'm trying to create a database for my company. I've got all the basics. I've found some information on functions to calculate time and dates, but I can't find specific information as to where to put it in the database and how to automatically calculate the times.

For example: We track date and time the project was entered into the system (automatic timestamp). The time it took the tech to get onsite. The length of time he was onsite and the overall completion time.

It's amazing that we've gotten this far by doing all of this by hand on handwritten tickets.