Why Create an Inventory Database ?

I've been making progress on my Inventory database-but slower than I expected. I have forgotten more database basics over the past 10 years than I thought. And I'm using a different database (OpenOffice Base-free!) than I worked with in the past (Lotus Notes.)
I still think it is the right move. Here's why:
I buy many yards of fabric at a time, 20-50 yards, of at least 4 different types. Yardage is cut, dyed in 3 yard lengths and is then sold in full and partial yards. I want to know:

1. How much total yardage of each type I purchase each year
2. What my cost per yard is including shipping and after shrinkage for each type
3. What dyed fabric I have in inventory by type, including length, price and selling venue (I have 3)
4. What I have sold, for what price and where
5. What I have in remaining inventory, dyed and undyed, for tax purposes
6. What sells the best by fabric type, color, venue.

Before deciding on a database I tried keeping records of what I bought and what I sold but that didn't tell me what I had on hand in dyed yardage. I calculated the cost per yard and used that in my pricing calculations but didn't think to include shrinkage. Come the end of the year I had to measure each piece of dyed and undyed fabric to come up with my inventory. And I have no good summaries of where the fabric sold, just exported lists from Etsy, ArtFire and my web site.
If I were buying piece goods (scarves, t-shirts) or were selling by the piece rather than by the yard I might be able to do this manually with several lists or spreadsheets. But, inventory rolls over from one year to the next. And I want more information, not just guesses, about what sells by fabric type, color, season and venue.
You may not need a database. For me, it is the only way I'll get the information I need going forward. I'm using January to get all of my 2010 purchases, dyed yardage and sales in order. No new fabric purchased until February-and since I really love dyeing, that will push me along. But I'm also really excited to know that I'll have a tool for building my business by knowing where it has been and where it is now.