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

Evaluate the null hypothesis, 1.Suppose you are given a dataset that consis...

1.Suppose you are given a dataset that consists of a random sample of tasters, on which the following variables were obtained: (y) Zpref = taste preference for green beans store

Define seek time, Define seek time. The time for repositioning the arm ...

Define seek time. The time for repositioning the arm is known as the seek time and it enhances with the distance that the arm is known as the seek time.

Database, 3. (10 points) Assume that you have been presented with the follo...

3. (10 points) Assume that you have been presented with the following relation for the Baxter Aviation database: Charters (Pilot#, Pilot name, Aircraft ID#, #seats, Village, Fligh

What are the three classes of sql expression, What are the three classes of...

What are the three classes of SQL expression? SQL expression consists of three clauses:  Select  From  Where

SQL, Ask Write the SQL code that will create the table structure for a tabl...

Ask Write the SQL code that will create the table structure for a table named EMP _1. This table is a subset of the EMPLOYEE table. The basic EMP_1 table structure is summarized in

What is an index as defined in oracle, Normal 0 false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Managing database, 10A.53 Code an Oracle Database trigger to enforce the ...

10A.53 Code an Oracle Database trigger to enforce the constraint that an employee can never change his or her department. 10A.54 Code an Oracle Database trigger to allow the

Explain the project-join normal form, Explain the Project-Join normal form ...

Explain the Project-Join normal form A relation R is in PJNF along with respect to a set of functional dependencies D if for all join dependencies of the outline *(R 1 , R 2 ,

2phase locking, we need example of 2phase locking

we need example of 2phase locking

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