Fifth normal form is concerned with :
Join Dependency
Each higher normal form removes a particular kind of redundancy. 2NF, 3NF and BCNF deal with functional dependencies, 4NF deals with multivalued dependencies, and fifth normal form (also called project-join normal form, PJNF) deals with join dependencies.
A relation is in 5NF when every non-trivial join dependency that holds on it is implied by its candidate keys. In other words, the relation cannot be split into smaller projections and rejoined losslessly unless the split is driven by keys, which removes the remaining redundancy that 4NF cannot catch.
Domain-key normal form is a separate, stronger ideal based on domain and key constraints, not the concern of 5NF. Multivalued dependency is the basis of 4NF, and functional dependency is the basis of 2NF, 3NF and BCNF.
Join Dependency option is correct.
Similar Questions
Which of the following is false ?
The Relation
Vendor Order (V_no, V_ord_no, V_name, Qty_sup, unit_price)
is in 2NF because :
Select the ‘False’ statement from the following statements about Normal Forms :
Consider the schema
R = {S, T, U, V}
and the dependencies
S → T, T → U, U → V and V → S
If R = (\(R_{1}\) and \(R_{2}\)) be a decomposition such that \(R_{1} \cap R_{2} = \phi\) then the decomposition is
Consider the following relational schemas for a library database :
Book (Title, Author, Catalog_no, Publisher, Year, Price)
Collection(Title, Author, Catalog_no)
with the following functional dependencies :
I. Title, Author → Catalog_no
II. Catalog_no → Title, Author, Publisher, Year
III. Publisher, Title, Year → Price
Assume (Author, Title) is the key for both schemas. Which one of the following is true ?
Which of the following statements is false ?
In a schema R(A, B, C, D, E, F, G, H), each field of R contains only atomic values.
F = {CH→G, A→BC, B→CFH, E→A, F→EG} is a set of functional dependencies so that F+ is exactly the set of FDs that holds R. The relation R is :
Which of the following relations can not be decomposed in to BCNF with a lossless join and dependency-preserving decomposition ?
Which of the following/s is/are FALSE statement?
A. An all key relation is always in BCNF since it has no FDs.
B. A relation that is not in 4NF due to nontrivial MVD must be decomposed to convert it into a set of relations in 4NF.
C. The decomposition removes the redundancy by the MVD.
D. 3NF is stronger than BCNF.
Choose the correct answer from the options given below:
For a database relation R(A, B, C, D) where the domains of A, B, C and D include only atomic values, only the following functional dependencies and those that can be inferred from them are :
A → C
B → D
The relation R is in _______.
Important Questions from Normal Form
Which of the following statement(s) is/are correct regarding a relation in second normal form?
I. It is in first normal form
II. Every non-key attribute is fully and functionally independent on the primary key
Which of the following normal forms specifically addresses and eliminates partial dependencies?
Consider a relational schema team(name, city, owner), with functional dependencies {name $\to$ city, name $\to$ owner}.
The relation team is decomposed into two relations, t1(name, city) and t2(name, owner). Which of the following statement(s) is/are TRUE?
In a relational database, which one of the following is CORRECT:
Which of the following is false ?
