We now have relational scheme R = {A, B, C, D, E, F, G } and the
following
functional dependencies:
And the Following MVDs:
Asking: Is this relation in the 4NF? Why? If it is not in 4NF, transform it into 4NF.
Fourth normal form (4NF):
Fourth normal form (4NF) is a level of database normalization
where there are no non-trivial multivalued dependencies other than
a candidate key. It builds on the first three normal forms (1NF,
2NF and 3NF) and the Boyce-Codd Normal Form (BCNF).
It states that, in addition to a database meeting the requirements
of BCNF, it must not contain more than one multivalued
dependency.
Properties – A relation R is in 4NF if and only if the following conditions are satisfied:
It should be in the Boyce-Codd Normal Form (BCNF). Also, a table should have at-least 3 columns for it to have a multi-valued dependency.
suppose there is a relation R = {A, B, C, D, E, F, G } with
functional dependency
set (D → AC). The relational R is decomposed into R1(ABCDEFG) and
R2(AD) which is dependency preserving
because FD D → AC is a part of relation R1(ABCDEFG).
Conclusion: - Given relational scheme is in 4NF.
We now have relational scheme R = {A, B, C, D, E, F, G } and the following functional dependencies: D → AC GA → C E → A GD → BF GD → E And the Following MVDs: C→→ A F →→ B GB →→ C Asking: Is this...
We have the attributes: {A, B, C, D, E, F, G}. Consider the following functional dependencies E, F → C E → F B → A, G A, E, F → C, G D → A C, D, F → B, E, G A → B B, E → D, G Mark all functional dependencies that are implied by the dependencies above: a). D,F --> E, F b). D,F --> A,F c) D,F --> A d) D,F -->G e) D,F...
Q3: Given a relational schema R = {A,B,C,D,E,F,G,H,1,J,K} and a set of functional dependencies F {A B C D E, E F G H I J,AI →K} and a key(R) = AI = 1. Is R in BCNF? If yes, justify your answer [5 points] 2. If no, explain why and decompose R for two levels only [10 points] 3. Check whether the decomposition in step 2 dependency preserved or not [5 points]
Consider the following relation R(A,B,C,D,E,G) and the set of functional dependencies F = { A → BCD BC → DE B → D D → A} Give a 3NF decomposition of the given schema based on a canonical cover
MySQL: Consider the following abstract relational schema: (A, B, C, D, E, F) Now assume the following functional dependencies: A -> B, C, D, E, F C -> B Note: This implies that A is a key. Is this database in 1NF, 2NF, 3NF, or BCNF? Why?
Consider the following relation: R(A,B,C,D,E) The following set of functional dependencies are ture on the relation R: FD: AB -> E, E -> D, AD -> C Which of the following sets of attributes does not functionally determine C? AC ABE BD AE AB
Here's a relation (R), its attributes and its functional dependencies (F): R(A, B, C, D, E) C D → B A → D D → C E → C What is the closure of AB ({AB}+)? What is the closure of F (F+)? [ set of closures for all LHS][each LHS on one line] What is the minimal set (cover) for F? Provide a key for relation R (a minimal set of attributes that can determine all attr.) Decompose the...
Language: SQL - Normalization and Functional Dependencies Part 4 Normalization and Functional Dependencies Consider the following relation R(A, B, C, D)and functional dependencies F that hold over this relation. F=D → C, A B,A-C Question 4.1 (3 Points) Determine all candidate keys of R Question 4.2 (4 Points) Compute the attribute cover of X-(C, B) according to F Question 43 (5 Points) Compute the canonical cover of F.Show each step of the generation according to the algorithm shown in class....
consider the schema R-(A,B.C,D,E) and the following set F of functional dependencies holds on R ABC CD-E B- D E-A Problem 2. Suppose that we decompose the relation schema R into R, -(A, B, C) and R, (C, D,E). Show that this decomposition is not a lossless-join decomposition.
Consider a relation schema R with attributes ABCDEFGH with functional dependencies S: S={B→CD, BF→H, C→AG, CEH→F, CH→B} Employ the BCNF decomposition algorithm to obtain a lossless decomposition of R into a collection of relations that are in BCNF. Make sure it is clear which relations are in the final decomposition and project the dependencies onto each relation in that final decomposition.
Consider a relation R(A,B,C,D,E) with the following functional dependencies: 8. AB C BCD CDE DEA (a) Specify all candidate keys for R. (b) Which of the given functional dependencies are Boyce-Codd Normal Form (BCNF) violations'? (c) Give a decomposition of R into BCNF based on the given functional dependencies. (d) Give a different decomposition of R into BCNF based on the given functional dependencies. (e) Give a decomposition of R into 3NF based on the given functional dependencies. Consider a...