2 votes 2 votes Consider the following relation R(A, B, C, D, E, F, G) and set of functional dependencies. F={BCD → A, BC → E, A → F, F → G, A→G, C → D} Which of the following is minimal cover of F? {BC → A, BC → E, A → F, C → D, A → G} {BC → A, B → E, A → F, F → G, C → D} {BC → A, BC → E, A → F, F → G, C → D} {BC → A, BC → E, A → F, C → D} Databases made-easy-test-series databases minimal-cover database-normalization + – Shivam Kasat asked Jan 4, 2019 • edited Aug 2, 2020 by soujanyareddy13 Shivam Kasat 2.8k views answer comment Share Follow See all 10 Comments See all 10 10 Comments reply Show 7 previous comments Shivam Kasat commented Jan 4, 2019 reply Follow Share got it @adarsh_1997 I thought that only minimal cover FDs implies Given FDs is needed, minimal cover should cover given FDs and Given FDs should also cover minimal cover. M i Right? 0 votes 0 votes adarsh_1997 commented Jan 4, 2019 reply Follow Share yes @Shivam Kasat thats right 0 votes 0 votes Shamim Ahmed commented Jan 5, 2019 reply Follow Share C is correct. 0 votes 0 votes Please log in or register to add a comment.
1 votes 1 votes Given that $R(A,B,C,D,E,F,G)$ and set of Functional dependencies$:F = \left\{BCD → A, BC→ E, A→ F, F→ G, C→ D, A→ G\right\}$ Lakshman Bhaiya answered Dec 20, 2018 Lakshman Bhaiya comment Share Follow See all 10 Comments See all 10 10 Comments reply Show 7 previous comments ayushsomani commented Sep 3, 2019 reply Follow Share @Lakshman Patel RJIT I am talking about Closure of (BC) when we remove BC gives E. (BCD)+ is correct. 0 votes 0 votes ayushsomani commented Sep 3, 2019 reply Follow Share @Lakshman Patel RJIT Can you find a quick method to solve this question - https://gateoverflow.in/116026/number-of-different-minimal-cover? 0 votes 0 votes Lakshman Bhaiya commented Sep 3, 2019 i edited by Lakshman Bhaiya Sep 3, 2019 reply Follow Share @ayushsomani Yes, you are right. But I write only which is required for answers. see this https://stackoverflow.com/questions/10284004/minimal-cover-and-functional-dependencies https://www.inf.usi.ch/faculty/soule/teaching/2014-spring/cover.pdf https://dba.stackexchange.com/questions/214669/how-to-solve-multiple-minimal-covers-for-functional-dependencies http://www.mathcs.emory.edu/~cheung/Courses/377/Syllabus/9-NormalForms/FD-equi.html https://gateoverflow.in/6346/is-canonical-cover-and-minimal-cover-the-same-thing 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes first delete D AND find the closure of remaining, ie- (BC+) = if you cand the D again then writing BCD WILL BE MORE COSLTY SO, SIMPLY WRITE IT LIKE- BC----->A krmanish043 answered Dec 20, 2018 krmanish043 comment Share Follow See 1 comment See all 1 1 comment reply Bikash Chaurasia commented Dec 22, 2018 reply Follow Share Thanks sir krmanish043 0 votes 0 votes Please log in or register to add a comment.
0 votes 0 votes answer can't be B, it doesn't covers F as in (B) it is given B$\rightarrow$ E, but to derive E we need both B and C $\therefore$ BC $\rightarrow$ E snaily16 answered Jan 4, 2019 snaily16 comment Share Follow See all 2 Comments See all 2 2 Comments reply Shivam Kasat commented Jan 4, 2019 reply Follow Share Closure(BC)=BECD Thus BC-->E in option B M i wrong? 0 votes 0 votes snaily16 commented Jan 4, 2019 reply Follow Share ya, so the correct answer is C {BC → A, BC → E, A → F, F → G, C → D} 0 votes 0 votes Please log in or register to add a comment.