2 votes 2 votes Que- R(ABCD) and fds are { A->B ,B->C,C->A} then number of candidate key is........? Explain please Databases databases database-normalization + – air1ankit asked Oct 17, 2017 air1ankit 516 views answer comment Share Follow See all 5 Comments See all 5 5 Comments reply Show 2 previous comments Shubhanshu commented Oct 17, 2017 reply Follow Share D is the Multi value Attribute, so it will be in every CK, and From the FD's we can easily see that A, B and C defining each other. So, CK {AD, BD, CD}. 1 votes 1 votes air1ankit commented Oct 17, 2017 reply Follow Share Thanks bro 0 votes 0 votes arch commented Oct 29, 2017 reply Follow Share y u said d ismultivalued? if any attribute not present in fd that means that attribute is multivalued?? please exlain. 0 votes 0 votes Please log in or register to add a comment.
Best answer 1 votes 1 votes Closure of A ,B and C give = ABC but D is missing so Candidate key will be AD ,BD,CD now we take closure of AD = ABCD , BD = ABCD , CD = ABCDso we get all attributes of Relation so AD is candidate key Rishi yadav answered Oct 17, 2017 • edited Nov 30, 2018 by Rishi yadav Rishi yadav comment Share Follow See all 0 reply Please log in or register to add a comment.