1 votes 1 votes Databases databases er-diagram + – jatin khachane 1 asked Dec 18, 2018 jatin khachane 1 781 views answer comment Share Follow See all 11 Comments See all 11 11 Comments reply arvin commented Dec 18, 2018 reply Follow Share 4.. because we have m:n relation.. so we will need 3 tables for each.. +1 table more because E is mvd.. 0 votes 0 votes jatin khachane 1 commented Dec 18, 2018 reply Follow Share can't we add MV attribute to relationship table forming ADE as key ? 0 votes 0 votes arvin commented Dec 18, 2018 reply Follow Share no brother ! if there is mva in any entity you need to take a separate table for that.. and if you want to use ADE. you could have kept in DEF only there might be very few difference between them(in terms of tuples).. 0 votes 0 votes Shivam Kasat commented Dec 18, 2018 reply Follow Share 4 is the correct answer a table for E1(A,B,C) a table for E2(D,F) and one more for its multi-valued attribute E(D,E1,E2..) a table for establishing the relationship between the two entities since their is a many-many relationship R(A,D) so total 4 tables :) 1 votes 1 votes jatin khachane 1 commented Dec 18, 2018 reply Follow Share @arvin But it is not causing any problem other than redundancy ? 0 votes 0 votes arvin commented Dec 18, 2018 reply Follow Share yes this is the only point you need to remove redundancy as lest as possible... 0 votes 0 votes akshat sharma commented Dec 18, 2018 reply Follow Share 4 tabe wil be required 3 from M:N and 1 from MV 0 votes 0 votes jatin khachane 1 commented Dec 18, 2018 reply Follow Share @arvin @Shaik Masthan Here nothing mentioned about redundancy only min relations asked..we can't do like this in 1 to M and 1 to 1 as there it violates key constraint but in M:N can't we merge MV attribute with relationship table... 0 votes 0 votes arvin commented Dec 18, 2018 reply Follow Share @jatin khachane 1 if nothing is mentioned than also you need to eliminate redundancy for efficient use of database... and if nothing is mentioned about redundancy and you are satisfied with that than only 1 relation is enough :) use 1nf with 100%redundancy. 0 votes 0 votes jatin khachane 1 commented Dec 18, 2018 reply Follow Share m not saying answer should be 3 ..I just mentioned my doubt :( if we do like this ADE as key..which normal will it violates ? 0 votes 0 votes arvin commented Dec 18, 2018 reply Follow Share @jatin khachane 1 aree bro :p i was just trying to make it simple. see brother if you have mva u need to have a new table... 0 votes 0 votes Please log in or register to add a comment.