I've been writing a Library management Java app lately, and, up until now, the main Library database is stored in a `.txt` file which was later converted to `ArrayList` in Java for creating and editing the database and saving the alterations back to the `.txt` file again. A very primitive method indeed. Hence, having heard on SQL later on, I'm considering to port my preexisting `.txt` database to mySQL. Since I've absolutely no idea how SQL and specifically mySQL works, except for the fact that it can interact with Java code. Can you suggest me any books/websites to visit/buy? Will the book Head First with SQL ever help? especially when using Java code to interact with the SQL database? It should be mentioned that I'm already comfortable with using 3rd Party APIs.