Finally got a number !!! At that level, there is no need to embark in using a RDBMS. In the very very long run, you may wish to convert it to a DB, but for now, let just stay with a single txt file well organized. With a SRE perfectly adapted to your request, it will take about 1 ms to get the answer. So for now, you will need to prepare for us a few of those real questions based on a real repertory of knowledge (not just test and useless stuff) and the real expected result. Based on that, we will be able to provide some guidances and maybe a startup code for you.