Explain the project-join normal form, Database Management System

Assignment Help:

Explain the Project-Join normal form

A relation R is in PJNF along with respect to a set of functional dependencies D if for all join dependencies of the outline *(R1, R2, ...,Rn) and R =  R1 U R2 U ..., URn at least one of the subsequent holds:

 *(R1, R2, ...,Rn) is trivial

 Each Ri is a superkey of R


Related Discussions:- Explain the project-join normal form

Binary relationships, One-to-one relationship: For every 1:1 relationshi...

One-to-one relationship: For every 1:1 relationship type R in the ER diagram including two entities E1 and E2 we take one of entities (say E1) preferably with total participatio

Integrity of a database enforced by integrity rules, Question: This Que...

Question: This Question refers to the database schema given in the Appendix. (a) The integrity of a database is enforced by integrity rules. Discuss what should happen on a

Difference between functions along with or without grouping, Explain the di...

Explain the difference between using functions along with and without grouping attributes in relational algebra. Give examples. Ans: Group functions are used to group data of

Describes the several relationship constraints, Describes the several relat...

Describes the several relationship constraints through giving suitable example? Constraints on relationships: There are two kinds of constraints on relationships. 1) Mapping

What is conceptual schema, What is Conceptual Schema? Conceptual Schema...

What is Conceptual Schema? Conceptual Schema - Conceptual schema elaborates the structure of the overall database for a community of users. It hides the details of physical sto

What is known as sequential file organization, What is known as sequential ...

What is known as sequential file organization? In the sequential file organization, the records are kept in sequential order, according to the value of a "search key" of every

What are the reasons of bucket overflow, What are the reasons of bucket ove...

What are the reasons of bucket overflow? Explain any two methods for solving this problem. Ans:  It is general for file structures to be divided into equal-length partitions, k

What is a database, What is a Database? To know what database is, we ha...

What is a Database? To know what database is, we have to start from data, which is the basic building block of any DBMS. Data: Facts, figures, statistics etc. having no pa

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd