Dear database forum,

I am getting closer to the final design. Sometimes I have a flash of understanding, but that usually goes away and is replaced by doubt and confusion.

Background: This is a Survey (not for a business or they would be in trouble) but for an academic requirement. (however, for your information...it is NOT worth a grade). Anyhow, it will have multiple (exclusive) choice, multiple (inclusive) choices, free text (minimal amount), and likert scale type of questions.

Basic Paradigm: It could be simplier,but I want to give it scalability. There are these tables: survey, section, question, answers, SurveyQuestions, itemTypes, and responses. The Answers table has a composite key of (survey, question, choice). Even though I don't necessarily need the survey* as part of the key...it is possible that the same question be on two different surveys that have different answer choices.

My primary questions: 1. do i need tables for each type of question (MC inclusive, MC exclusive, etc.)? 2. in the response table should i record all values even the values that are empty. ie.

Which animals do you like?
A. Dog
B. Cat
C. Pig

suppose participant answers A and B, so should I record this into the response table like this

Choice 1 (Dog)= 1
Choice 2 (Cat)= 1
Choice 3 (Pig)= 0

or just keep track of the "yes"'s
Choice 1 (Dog)= 1
Choice 2 (Cat)= 1


here is my design so far, look at my design and critic it please.

*P.S. basic design by Barry Williams database answers.

P.s.s. is the triple relationship necessary?

in general is a "tree" the optimal structure (as in my attached relationship table) or a "cycles" acceptable and/or necessary?