【简答题】(10X4 分 =40 分 ) Directions: Fill in the blanks with the words and expressions from a list of choices given in a word bank following the passage. Each choice should be used only once. (Chris sees Mr....
【多选题】Consider a relation with schema R(A,B,C,D) and functional dependencies A → C, BC → D. Which of the following FDs are BCNF violations? (This is a multiple choice question)
【多选题】Consider a relation with schema R(A,B,C,D) and functional dependencies AB → C, D → A. Which of the following are followed from the given FD’s? (This is a multiple choice question)
【多选题】Consider a relation with schema R(A,B,C,D) and functional dependencies AB → C, D → A. Which of the following are superkeys of R? (This is a multiple choice question)