Hi Dr. Sun,

1. In your example, db_class_size is an after-trigger, and the db_class_size() function tests "if l_class_size > 30". Is this equivalent to creating a before-trigger and testing "if l_class_size = 30"?

2. The special variables "new" and "old" can only be used with an after-trigger, not a before-trigger, correct?

3. Is the entire midterm going to open-internet as well? (i.e. can we access the PostgreSQL documentation during the midterm)?

Thank you.

- Peter Tran