0 votes 0 votes The correct answer is a and d. I just wanted to know that why not b and c. It is possible that it may be speed and color is also a candidate key. If you have any clarification on this let me know!!! Databases self-doubt candidate-key superkeys rdbms + – gateexplore asked Sep 22, 2023 gateexplore 468 views answer comment Share Follow See all 3 Comments See all 3 3 Comments reply ssingla commented Sep 24, 2023 reply Follow Share the question already mentions all the superkeys which are in the relation. candidate keys are superkeys too. B,C option is not mentioned in the list of superkeys which means they cannot be candidate keys 0 votes 0 votes Chandrabhan Vishwa 1 commented Oct 23, 2023 reply Follow Share i think ans only A because here given super keys are not All super keys. 0 votes 0 votes Sajal Mallick commented Nov 20, 2023 reply Follow Share As mentioned in the question that superkeys are:- {VID},{VID,MODEL},{SPEED,COLOR},{SPEED,COLOR,MODEL}. According to concept of keys:- “Every candidate key is super key but all super keys are not candidate key.” If {VID,Model} is candidate key then {VID} cannot be superkey. But if {VID} is candidate key then {VID,MODEL} can superkey. Likewise for other two it is same. So, B and C option is incorrect. 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes I just wanted to know that why not b and c. It is possible that it may be speed and color is also a candidate key. As mentioned in the question, {speed, color} combo is superkey alone speed and color is not a superkey. So answer is A & D geetaseshapallli answered Oct 23, 2023 geetaseshapallli comment Share Follow See all 0 reply Please log in or register to add a comment.
0 votes 0 votes all possible keys are called as super keys and minimal super keys ( that cant be more divided ) is only candidate key option A is correct but question is asking for all possible keys so from option only A and D is correct xtyhasan answered Nov 20, 2023 xtyhasan comment Share Follow See all 0 reply Please log in or register to add a comment.