BCNF decomposition which generates redundant relations (as for 3NF)
Sometimes the 3NF decomposition algorithm generates redundant relations, where all attributes of some R_i already appear in another R_j. The algorithm is supposed to delete such redundant relations. I...
View ArticleWhy is relation not in BCNF?
I have the relation (A,B,C,D,E) and the FDs: E,B,C->D A,B->C E,B,D->C E,A,B->D The candidate key is E,A,B. I do not understand why this relation is not in BCNF because the candidate key...
View ArticlePrime attribute dependant on another prime attribute allowed under BCNF?
I have been studying DBMS ans I have a question that I got conflicting answers to: Is prime attribute that is dependant on another prime attribute allowed under BCNF? Meaning P->P. I know that...
View ArticleHow to decompose into BCNF while preserving all functional dependencies
I have a relation R = {A,B,C} and F={AB -> C , C -> B}. In order to check if R is in BCNF. I checked if AB and C are both superkeys and since C is not a superkey I conclude R is not in BCNF....
View Article