You've basically got three options:
- Use a generic program, like Excel or Google Sheets. This has the advantage of flexibility; the disadvantage being of course you literally have to start from scratch, and decide what exactly you want to be adding to your database. Another advantage of using a popular resource is the file format is unlikely to become totally forgotten or unreadable.
- Use a bespoke coin database software package. I personally use one called "Coin Organizer Deluxe", it's been around for decades and you have to pay a one-off fee for use.
- Use a cloud-based or website-based database. This has the advantage of being accessible wherever you go and remaining accessable even if you upgrade your hardware, and you don't have to worry about making backups and keeping them safe. Disadvantage: you can only access it when your internet connection is working, and it may be more vulnerable to data-theft and hacking.
Whichever you choose, the main drawback with a database is the time you need to spend creating it. Which is why I always recommend, if a collector is at all feeling inclined to create a database or you think that might become useful in the future, to start early, while your collection is still small. Don't put it off until you think your coin collection is big enough to make it worthwhile, because you're just making your job harder for yourself. Sitting down and creating a 600-entry database is ten times faster than sitting down and creating a 6000-entry database.
I've got 14,309 coins in my collection: I need a database of some kind, just to keep track of what I've already got, and to be able to find stuff without having to search the whole collection for it. But I'd never try to start creating a database for my collection now; it'd take me several years to enter 14,309 coins. But, I didn't have to - I've been keeping a "coin database" ever since I was 12 and had just a few hundred coins. Granted, I had to start all over again when my Commodore 64 became obsolete, but even so, it wasn't too hard to create a 1000 entry database on the PC when I already had all the data collated and sorted; I could copy it across relatively easily.
The biggest headache I've had with database maintenance is having to upgrade the software. When my original coin database program became obsolete in 2005, I needed to export and import the data to a new database. I finally found a new database that allowed the import mostly flawlessly - except for a couple of data fields that refused to transcribe themselves properly ("purchase date" was one such recalcitrant field, I recall). The new database also had a bunch of new fields I had never entered data for before, that I thought would still be useful. So I had to go back through the database (which was 6630 entries long at the time) and manually correct the data on each entry. It literally took me two years of free time before I finished the job.
The second-biggest problem was entirely self-made: way back when I was 12, I'd created a system where every coin was assigned a unique four-digit collection number, the "Sap number" (yes, I did actually call it that at the time) starting from "0001". Which of course meant I had to re-number everything once I hit 10,000 coins back in 2011, which meant having to add that extra zero to the "Sap number" field for 9999 database entries. Fortunately, I discovered "keyboard macros", which highly automated that process.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis