It's my first job, I'm still a student, I want to make sales software for a liquor store, with a local database, the language I use is java and I do not know which database to use, in the long run many will be saved data and I do not want to be congested or no longer allow me to save more data if it has a limit of data per table.
If your system, you will connect via intranet (locally) I would recommend that you use MySQL, it is a very reliable base and allows you to generate multiple options for your application. The requirements for your server, which in this case can be your own machine, considering that you are the administrator of the application you would need (something very accessible):
- Procesador Core 2 Duo.
- RAM 4 GB (recomendable 8 GB).
- Windows 7 ó si prefieres puedes utilizar Linux Ubuntu 14.04 LTS (genial).
- DD 250 GB
Considering that your base is for almost 15,000 to 20,000 transactions per month, you would have plenty of it and it would work very well for you. Besides MySQL is free and has a lot of support, it is one of the most stable bases there is.
I hope it helps you decide on your requirements.
your question is a bit open and the most appropriate answer will be what meets your requirements of the system to design, the budget you have, this to choose a commercial bd engine or an open source. For you to choose in a better way, I recommend you to ask yourself a series of questions and depending on that, select the one that best suits your needs.
You have alternatives such as Oracle, MS SQL Server, or My Sql, Mongo DB, etc.
First the size of your table (so to speak), depends more on the operating system than the type of BD, but what can influence is the storage engine, I recommend using InnoDB .