Assignment 1 FAQs


  1. How can I access DB2 system from off-campus?
  2. You will need to connect VPN first when you are off-campus. Download and installed the VPN client here. Once you login VPN, and then try to connect the db server via SSH.

  3. What is website of Avenue to Learn ?
  4. Click here.

  5. How to upload the script to DB2 system ?
  6. You can use SSH software. More detail is here.

  7. Do we need to complete an algebraic proof for question 2? Can I use an example to prove?
  8. I don't expect a formal mathematical proof for question 2. But you will need to clearly explain why it is or it's not commutative. You can't simply prove by example.

  9. Can I use composite attribute for E-R Model in question 4?
  10. I have no problem for you to use composite attributes or any other techniques from the textbook. However, you need to ensure using them make sense for the requirements of assignment question.

  11. What's the primary key for a relationship table?
  12. If the relationship is a many to many relationship, then the primary key is the combination of of the two primary keys from the participated entity sets. If the relationship is many to one, then the primary key is the primary key of the many side participated entity set. If the relationship is one to one, then you can choose any side primary key of the participated entity set. See page 14 on lecture slides, Likes is many to many, pk=(drinker, beer); Favorite is many to one, pk=(drinker); Married is one to one, pk=(husband) or (wife).