What is a recursive relationship, Database Management System

Assignment Help:

Question:

(a) Can a set of data requirements be correctly modelled by two or more different ER diagrams? Explain your answer. You may use a small example, if you think it will help your explanation.

(b) What is a recursive relationship? Give an example of a many to many recursive relationship.

This question refers to the Appendix where the relational schema for an online DVD rental system is defined.

(c) Express the following queries using relational algebra:

(i) Find all DVD titles with their certificate being ‘15' and their type name being ‘Drama'

(ii) Find names of all members and the titles of DVDs, which they have rented between 1st

May 2007 and 31st
May 2007

(iii) Find names of all the members who have rented any DVD with type name ‘Comedy' but not any DVD with Type name ‘Action'


Related Discussions:- What is a recursive relationship

Concept of foreign key, Fundamentals of Database Management 1. Explai...

Fundamentals of Database Management 1. Explain the concept of Foreign Key. How a foreign key differs from a Primary Key? Can the Foreign Key accept nulls? 2. With a necess

Give the general form of sql query, Give the general form of SQL query? ...

Give the general form of SQL query? Select  A1, A2............., An From  R1, R2..............., Rm Where  P

Define page, Define page. The database is partitioned into some number ...

Define page. The database is partitioned into some number of fixed-length blocks, which are referred to as pages.

Assignment SQL Management Server 2012, Have database built but having probl...

Have database built but having problems with some questions that go with the database

Transaction managenment, can you please explain with the help of suitable e...

can you please explain with the help of suitable example the difference between conflict equivalence and conflict serializability?

Using sql create a view rs for the relations r and s, Using SQL create a vi...

Using SQL create a view RS for the relations R and S. The view consists of the columns A and D renamed as X and Y in that order. Insert a tuple into it. Show the contents of t

What is conceptual model, What is conceptual model ? A conceptual model...

What is conceptual model ? A conceptual model is a independent of both hardware and software.

Requirements for your cache simulator, Using your cache simulator and using...

Using your cache simulator and using smalltex.din as your memory trace determine the total miss rate, compulsory miss rate, capacity miss rate, and conflict miss rate for the follo

What is trigger, What is trigger Triggers are statements that are imple...

What is trigger Triggers are statements that are implemented automatically by the system as the side effect of a change to the database.

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