0 0 votes Databases + – ben10 1.6k views answer comment Share Follow Print 0 reply Please log in or register to add a comment.
1 1 vote Two minimal covers are possible : A->B, B->C, C->A AND A->C, C->B , B->A Shiv Gaur answered Aug 19, 2018 Shiv Gaur comment Share Follow See all 7 Comments 7 7 Comments reply Show 4 previous comments Shaik Masthan commented Aug 20, 2018 reply Follow flag @Shiv Gaur, yes procedure is correct... but my question is A->C, B->C,C->AB A->BC, B->A,C->A ( As Iqra Islam said ) A->B,B->AC,C->B isn't these are minimal? i didn't find any redundant term or FD in that. 0 0 replyShare Shiv Gaur commented Aug 20, 2018 reply Follow flag I don't know the exact reason but I guess , when we talk about minimal cover of a given FD F, It is a minimal set of FDs that is equivalent to the given FD F. Here {A->C, B->C,C->AB} covers the given F but it could be further split to {A->C, B->C,C->A, C->B} ie 4 FDs and we already have A->B, B->C, C->A and A->C, C->B , B->A ie 3 FDs that's why we split the RHS in first step 0 0 replyShare Shaik Masthan commented Aug 20, 2018 reply Follow flag @Shiv Gaur, Those are also SHOULD BE minimal covers, note that minimal covers are not unique. compare this in DIGITAL LOGIC all those are irreducible, but which you mentioned are minimal expression but in DBMS we don't have two terminologies... therefore all are minimal covers only 0 0 replyShare Please log in or register to add a comment.
1 1 vote Two minimal covers are possible. vikas999 answered Aug 19, 2018 vikas999 comment Share Follow See 1 comment 1 1 comment reply Shaik Masthan commented Aug 20, 2018 reply Follow flag @vikas999, yes procedure is correct... but my question is A->C, B->C,C->AB A->BC, B->A,C->A A->B,B->AC,C->B isn't these are minimal? i didn't find any redundant term or FD in that. 0 0 replyShare Please log in or register to add a comment.