My bad, I should have being more specific. Yes, TripeHound is making a good point. Something, I will think about it in my future projects. In this case, I'm probably OK. Data is simple financial stock market data with UNIQUE date, then columns: open, high, low, close and volume. That's where I have most tables. Before I was writing data into simple txt files (CSV) and I had one file for each stock. Now I have stocks.db and each table is one stock ticker. I like this so much better :) In this case, I'm probably OK with my schema? Also, these are all learning, hobby projects. P.s. Interestingly, I created account, I'm logged in but I still come out as anonymous ;)