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

List and describe the different types of indexes, Question 1 Indexes are o...

Question 1 Indexes are ocasionally defines on a single field of a file called an indexing field. List and describe the different types of indexes Question 2 Consider a book i

Higher software development cost, Drawbacks of Data Distribution: The prim...

Drawbacks of Data Distribution: The primary drawbacks of distributed database systems are the added complexity needed to ensure proper coordination between the sites. This increas

Trigger , Flights(FlightNo, DeptDateTime, Origin, ArrivalDateTime, Destinat...

Flights(FlightNo, DeptDateTime, Origin, ArrivalDateTime, Destination, Capacity, SoldSeats) Tickets(FlightNo, Seat, CustID) Where - flightNo is the PK of the flights table - DeptDa

Write short notes on data ware housing, Write short notes on data ware hous...

Write short notes on data ware housing? Data ware housing applications needs the transformation of data from many sources into a cohesive reliable step set of data configured a

What is the error handling, What is the error handling Traditionally, b...

What is the error handling Traditionally, bits have been sent over line lacking any error correcting scheme in physical layer. The presence of the CPU in each modem makes it po

Cataloguing, differences between a classified catalog and a dictionary cata...

differences between a classified catalog and a dictionary catalog

What is nested trigger, What is Nested Trigger? A trigger can also havi...

What is Nested Trigger? A trigger can also having INSERT, UPDATE and DELETE logic within itself, so when the trigger is fired because of data modification it can also cause ano

Logical operators-logical operators, Logical Operators Rules of Preced...

Logical Operators Rules of Precedence: Order evaluated Operator 1 All comparison operators 2

Define outer union operation of the relational algebra, Define outer union ...

Define outer union operation of the relational algebra. Compute the outer union for the relations R and S given below. Outer Join - If there are any values in one tabl

Assign, #quesDefine a job scheduling strategy that will meet business requi...

#quesDefine a job scheduling strategy that will meet business requirement of reporting availability by 6am CST for the following cubes? Show the job scheduling dependencies in a pi

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