What are the general transformation rules, Database Management System

Assignment Help:

What are the General Transformation Rules for Relational operations? 

Ans: The transformation rules transform one relational algebra expression to AN

EQUIVALENT ONE 

1. Employed by the query optimizer to optimize query tree 

2. Any type of rule, if applied, ensures that the resultant tree is equivalent → resulting execution plan is equivalent 

 General Transformation Rules is as follow:

1. Commutativity of s: The s operation is commutative: 

  • sc1 (sc2(R)) = sc2 (sc1(R))
  • More selective selections first

Related Discussions:- What are the general transformation rules

NORRMALIZATION, Home based assignment Consider an ORDER table with the foll...

Home based assignment Consider an ORDER table with the following attributes: • Order Number (ONo),Customer Number (CNo),Customer Name (CNa),Item Number (INo),Unit Price (UP), Quant

What is meant by the degree of relationship set, What is meant by the degre...

What is meant by the degree of relationship set? The degree of relationship type is the number of participating entity types.

BCA, Ask qu. Write a XML with database with book details (Book ID, Title, A...

Ask qu. Write a XML with database with book details (Book ID, Title, Author, subject, published year, language, vendor, and price).estion #Minimum 100 words accepted#

Data integrity, You are required to implement integrity constraints within ...

You are required to implement integrity constraints within the database to enforce the following requirements:  For Projects: Start date must be supplied. Start date cannot be i

What are the factors into account when choosing a raid level, What are the ...

What are the factors to be taken into account when choosing a RAID level? A) Monetary cost of extra disk storage requirements. B) Performance requirements in terms of number

Can a filed occur in several field groups, Can a filed occur in several fie...

Can a filed occur in several field groups. Yes.  But it leads to redundant data redundancy.

What is the use of a slotted-page structure, What is the use of a slotted-p...

What is the use of a slotted-page structure and what is the information are there in the header? The slotted-page structure is used for organizing records within a one block.

What are the concurrency issues, Concurrency issues Data integrity...

Concurrency issues Data integrity: Threads accessing same object need to be synchronized, such as: banking account. Deadlock: One or more threads in system are perman

Draw an er diagram with primary key for a farm, Draw an ER diagram that rep...

Draw an ER diagram that represents the information described below. Show all entity sets, relationship sets, primary keys, and the mapping cardinality of the relationship sets.

converting eerd, Create centralized relational database using Top down met...

Create centralized relational database using Top down method- Construction of Logical Model: Translation EERD into Relational Schema: Use the 8 steps algorithm of converting EERD

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