We have always had databases. From our very first 512 Mac in 1986, we have had lists of addresses, pedigrees, CDs, software, and artwork. We have sent out show flyers, progress reports, requests for grant applications, and Christmas cards using labels printed from databases. So, of course, I have a database of all my threads and patterns.
I can even print out a list of needed DMC thread colors when JoAnne's or Michael's has them on sale. I can then take this printed list with me when I go to buy threads. But as with any data on a computer, the data is only as good as your willingness to update it. I thought I had a good handle on my DMC threads (though I am woefully behind updating my Rainbow Gallery threads), but when I went to pull threads for my last two projects, I found out that I was not as up-to-date as I thought I was. Obviously I had been buying thread, but not actually updating the database that the thread was purchased. And some threads were in the database, but not put away in the bags where they belong.
This is how I organize my DMC threads. Every color gets its own bag. The bag has a printed label (on Avery 8167 Return Labels, the same ones my husband uses for labeling slides) from my database with the color number and the color name. [Beware: Different designers can and have given different color names to the same DMC color number. Always select threads by the color number.]
When I need to pull threads for a project, I can get individual bags out and put them on a Project Ring. I do have to remember to "check out" the bag in the database. This ring is for a cross stitch project called Three Gables.
This is the box of rings I keep all my DMC floss in. Each ring is in color number order. I know most stitchers have some sort of system for keeping track of their floss. This is mine. I am grateful to the stitchers who recommended the Floss•Away system. I have tried other systems that required you to wind bobbins or hook the floss over bars, but I find this the easiest system that I have ever used.
Now all I have to do is update the database and print out a few labels for new colors that I bought, but didn't enter.
Computer neepery: Excel is not a database. Excel is good for pushing around numbers, but not so good for keeping track of many-to-many relationships. For many years we used a Macintosh only database called Helix (or Double Helix or Helix Express). It was truly relational, but had an odd "objective" programming structure and very poor reporting. Still, both my husband and I knew it inside and out. It was "non-programmy" enough that my husband, the artist, could use it. Unfortunately it was not supported by any company for many years, so in order to use a database that other people actually knew, we have been moving all of our databases to Filemaker Pro 8.5. It looks like this program will be around for a while, even if it is driving me crazy right now.