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

Explain the concepts of relational data model, Explain the concepts of rela...

Explain the concepts of relational data model? Relational Data Model - The relational model was first introduced through Prof. E.F. Codd of the IBM Research in the year 1970

Write the sql code, Express the following queries in SQL: (a) Write the...

Express the following queries in SQL: (a) Write the SQL code that will create ALL the four tables given in the appendix. Your answer should not contain the primary key and

What is candidate key, What is Candidate Key Super Key or Candidate Ke...

What is Candidate Key Super Key or Candidate Key: It is such an attribute of a table that can uniquely recognize a row in a table. Generally they have unique values and can n

Provide the steps involved in ethical analysis, Question : Mr. Smith Ha...

Question : Mr. Smith Harry has a car manufacturing company which has recently integrated management information system. He wishes to obtain more information on ethics and socia

Shared lock or read lock, Shared lock or Read Lock It is requested ...

Shared lock or Read Lock It is requested by a transaction that needs to just read the value of data item. A shared lock on a data item does not permit an exclusive lock

#title., WHY SHOULD NULL IN A RELATION BE AVOID AS possible?

WHY SHOULD NULL IN A RELATION BE AVOID AS possible?

Give an example of enforcement in typing, Give an example of enforcement in...

Give an example of enforcement in Typing. You can understand the idea of enforcement as it makes sure objects of dissimilar classes may not be interchanged as below:  Exampl

Describe five main functions of a database administrator, Describe five mai...

Describe five main functions of a database administrator. Ans: A database administrator (DBA) is a person who is accountable for the environmental aspects of a database. Genera

Entity - relation modeling and transformation, Represent the following scen...

Represent the following scenarios with E-R diagrams drawn using the ER Assistant software. The diagrams should indicate cardinality and optionality of relationships. Transform each

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