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

Datawarehouse, 1) Define a job scheduling strategy that will meet business ...

1) Define 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 pict

Concurrent transactions-backup and recovery, Representing complex relations...

Representing complex relationship among data A database may contain varieties of data interrelated to each other in numerous ways. A DBMS must have the capability to represent

Query, Use a Set operator to create a list of academics who have written or...

Use a Set operator to create a list of academics who have written or co-written less than 5 papers and also have greater than 3 interests. List their academic number in the output.

Aggregation, Design a database for an airline.The database must keep track ...

Design a database for an airline.The database must keep track of customers and their reservations,flights and their status, seat assignment on individual flights and, the schedule

Ldb hierarchy there should exist one get statement, It is mandatory that fo...

It is mandatory that for every table in the LDB hierarchy there should exist one GET statement in the report. False.  It is not essential.

What are the two types of indices, What are the two types of indices? T...

What are the two types of indices? The two types of indices are:- A)     Dense index B)      Sparse index

Explain the term- signal-to-noise ratio, Explain the term- signal-to-noise ...

Explain the term- signal-to-noise ratio A signal-to-noise ratio of 20 dB means that S/N = 100. As log2101 is around 6.658, the Shannon limit is around 19.975 kbps. The Nyquist

List the types of authorization, List the types of authorization. A) R...

List the types of authorization. A) Read authorization B) Write authorization C) Update authorization D) Drop authorization

What is a block and a block number, What is a block and a block number? ...

What is a block and a block number? A block is a contiguous sequence of sectors from a single track of one platter. Every request specifies the address on the disk to be refere

List some instances of collection types, List some instances of collection ...

List some instances of collection types? a) sets b) arrays c) multisets

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