User Account

All Pages

Prove that the decomposition of r into r1 and r2 is lossless

Assignment Help Database Management System
Reference no: EM13509339

1.Prove that an MVD X →→ Y over a relation R can be expressed as the join dependency ;: {XY, X(R − Y )}.

2.Let R be a relation schema with a set F of FDs. Prove that the decomposition of R into R1 and R2 is lossless-join if and only if F+ contains R1 ∩ R2 → R1 or R1 ∩ R2 → R2.

Reference no: EM13509339

Questions Cloud

Calculate the amount of income from the partnership : Quince Interests is a partnership with a tax year that ends September 30, 2012. During that year, Potter, a partner, received $3,000 per month as a guaranteed payment, and his share of partnership income after guaranteed payments was $23,000.
Estimate the temperature of the tungsten filament : A common flashlight bulb is rated at 0.108 A and 3.28 V (the values of current and voltage under operating conditions). estimate the temperature of the tungsten filament
Calculate the total amount of stockholders equity : Reeves, Inc., sold 1,000,000 shares of $25 par value common stock at $30. It subsequently repurchased 100,000 of those shares at $50 per share and then sold 70,000 of those shares at $55.
What balance will be assigned to the noncontrolling interest : What balance will be assigned to the noncontrolling interest in the consolidated balance sheet if Helms Company pays $90,000 to acquire 75 percent ownership in Rohan and goodwill of $20,000 is reported?
Prove that the decomposition of r into r1 and r2 is lossless : Let R be a relation schema with a set F of FDs. Prove that the decomposition of R into R1 and R2 is lossless-join if and only if F+ contains R1 ∩ R2 → R1 or R1 ∩ R2 → R2.
How many excess electrons or protons reside on the drop : A small drop of water is suspended motionless in air by a uniform electric field that is directed upward and has a magnitude of 6880 N/C. How many excess electrons or protons reside on the drop
Which categories are used to determine factory overhead : which are NOT used to determine Factory Overhead and why. which categories ARE used to determine Factory Overhead.
Find the change of momentum of the astronaut : An astronaut weighs 92.5 kg on earth. While floating in space he pushes the side of his spaceship with a force of 150 N for .20 seconds. Find the change of momentum of the astronaut
Wht is the mass of the car moving to the left : Two toy cars resting on a frictionless table top are separated by a spring compressed by tying it with a thread. wht is the mass of the car moving to the left

Reviews

Write a Review

Database Management System Questions & Answers

  Explain denormalized table in normal form

The DBA denormalized some of the data in the Premiere Products database to improve performance. Which field or fields cause the table to no longer be in third normal form? In which normal form is the denormalized table?

  Create a corresponding xmlschema file

A simple database with a single table contains data concerning car registration. The table contains four fields that store data relating to registration number (unique), make of car, year of manufacture and car colour

  Prove that the algorithm for decomposing a relation schema

Prove that the algorithm for decomposing a relation schema with a set of FDs into a collection of BCNF relation schemas as described in Section 19.6.1 is correct (i.e., it produces a collection of BCNF relations, and is lossless-join) and terminates.

  Map the erd to create the relational model

Map the ERD to create the relational model corresponding to the described application. Basically, list the CREATE TABLE statements with the attribute names, and appropriate data types.

  What is the value of the symmetric key

Suppose Fred sees your RSA signature on m1 and m2, (i.e., he sees (m1d mod n) and (m2d mod n)). How does he compute the signature on each of m1j mod n (for positive integer j), m1-1 mod n, m1 x m2 mod n, and in general m1j m2k mod n (for arbitrary..

  Computing functional dependencies

Compute the functional dependencies which exist in following table. After determining the functional dependencies, transform this table to an equivalent collection of the tables which are in third normal form.

  Mention various steps required to draw an e-r diagram draw

mention various steps required to draw an e-r diagram. draw an e-r diagram for student information system. mention all

  Requirementscreate a database from scratch that contains at

requirementscreate a database from scratch that contains at a minimum the elements listed below. the type of database

  Write a 2 page research paper on the turing and von neumann

write a 2 page research paper on the turing and von neumann models. compare and contrast each and discuss which model

  Briefly how to make use of indexes such as b+ tree

Summarize briefly how to make use of indexes such as B+ tree or a hash indexes in selection, projection, and join operations?

  Identify three potential users and design subschema for each

Identify three potential users and design a subschema for each. Justify your design by explaining why each user needs access to that data element.

  Describes the movement of inventory

Create a decision table that describes the movement of inventory and draw a decision tree that describes the merchandise inventory management process.

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!

Submit Assignment

Academics

Major Subjects

Majors

Get In Touch

whatsapp: +1-415-670-9521

Phone: +1-415-670-9521

Email: [email protected]

TERMS & POLICIES

HELP & SUPPORT

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