Tuples-attributes , Database Management System

Assignment Help:

Consider a relation s over the attributes A and B with the following characteristics:

  • 5,000 tuples with 10 tuples per page
  • A 2-level B+ tree index on attribute A with up to 100 index entries per page
  • Attribute A is a candidate key of s
  • The values that the attribute A takes in relation s are uniformly distributed in the range 1to 100,000.

(a)    Assuming that the aforesaid index on A is unclustered, estimate the number of disk accesses needed to compute the range query σA>1000 ^ A<6000 (s).

(b)   What would be the cost if the above index were clustered? Explain your reasoning.

 


Related Discussions:- Tuples-attributes

Define single value and multivalued attribute, Define Single Value and Mult...

Define Single Value and Multivalued attribute Single value attribute comprise a single atomic value for an entity and multivalued attribute may have much more than one value f

What is a view, What is a view?  Make a view of EMP table named DEPT 20, to...

What is a view?  Make a view of EMP table named DEPT 20, to display the employees in department 20 and their annual salary.  Ans:  View is a virtual table that does not consist

What is the purpose of storage manager, What is the purpose of storage mana...

What is the purpose of storage manager? The storage manager is responsible for the following a) Interaction with the file manager b) Translation of DML commands in to low

What is the disadvantage of a call by reference, What is the disadvantage o...

What is the disadvantage of a call by reference? During a call by reference damage or loss of data is not restricted to the subroutine, but will instantly lead to alters to th

Design and building a distributed information system, The scenario You ...

The scenario You have been approached to design and implement a prototype of a distributed information system for a national car part retail outlet chain. The company comprises

User error-database errors, User error :  This contains errors in the progr...

User error :  This contains errors in the program (e.g., Logical errors) with errors made by online users of database.  These types of errors can be avoided by applying some check

Describe substring comparison in sql, Describe substring comparison in SQL....

Describe substring comparison in SQL. For the relation Person (name, address), write a SQL query that retrieves the names of people whose name starts along with ‘A' and address co

Sql, find the name of supplier who supply some red part

find the name of supplier who supply some red part

Greater potential for bugs and increased processing overhead, Greater poten...

Greater potential for bugs: Since the sites of a distributed system operate simultaneously, it is more complex to ensure the correctness of algorithms. The art of constructing dis

Keys, it can be possible to create any table without primary key

it can be possible to create any table without primary key

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