Database for storing exam questions

I have been doing a project for the high school students. I am using Moodle as my LMS. My main goal is to create a database which will be kept offline at all time but data can be imported to moodle when I needed. I should mention here that moodle only import certain type of data for example gift, xml. Type of database:mysql /oracle Type of data I would like to store- multiple questions and case study based open and closed end questions. Type of Structure I am looking for- level or class(this database will have 10 level from year1 students questions to year10 students question)>>course( that tells which course from which the questions have been made>> sections(which section individual questions belong to), each course has 20 sections.>>questions (the questions type will be divided into type- Multiple questions and case study based question which could be open ended questions or close questions. each questions must be flaged either easy normal difficult like this. Query- can have query based on type of course, section, question type. A user should be able to extract the questions from the database as xml and import to moodle. A user have the interface to enter data into the database.