Solution-List whether the index matches the given selection

List whether the index matches the given selection condition

Assignment Help Database Management System

Reference no: EM13336567

Question 1

Athabasca University has about 32,000 students between the ages of 17 to 60. Consider the AU student relation with the following schema:

Students (stud-id: integer, stud-name: string, gpa: integer, age: real)

For each of the following indexes, list whether the index matches the given selection conditions. If there is a match, list the primary conjuncts.2

1. A B+-tree index on the search key Students.stud-id.

a. σ Students.stud-id < 28,000 (Students)

b. σ Students.stud-id = 28,000 (Students)

2. A hash index on the search key Students.stud-id.

a. σ Students.stud-id < 28,000 (Students)

b. σ Students.stud-id = 28,000 (Students)

3. A B+-tree index on the search key Students.stud-id, Students.age.

a. σ Students.stud-id < 28,000 and Students.age = 21 (Students)

b. σ Students.stud-id = 28,000 and Students.age> 21 (Students)

c. σ Students.stud-id = 28,000 (Students )

d. σ Students.age = 21 (Students )

4. A hash-tree index on the search key Students.stud-id, Students.age .

a. σ Students.stud-id = 28,000 and Students.age = 21 (Students)

b. σ Students.stud-id = 28,000 and Students.age> 21 (Students)

c. σ Students.stud-id = 28,000 (Students )

Reference no: EM13336567

Questions Cloud

What is the cost of joining r and s using a sort-merge join : What is the cost of joining R and S using a page-oriented simple nested loops join? What is the minimum number of buffer pages required for this cost to remain unchanged?

What is the total i/o cost for sorting this file : How many sorted subfiles will there be after the initial pass of the sort, and how long will each subfile be?

What is the carts final velocity : A 100 N force has a horizontal component of 60 N and a vertical component of 80 N. What is the cart's final velocity

Calculate the pressure of the gas on the walls : One mole of oxygen molecules occupies a cubic vessel of side length 10 cm at a temperature of 18 C. Calculate the pressure of the gas on the walls

List whether the index matches the given selection condition : Athabasca University has about 32,000 students between the ages of 17 to 60. Consider the AU student relation with the following schema.

Find an expression for the velocity vs distance : Find an expression for the velocity vs. distance.

Briefly how to make use of indexes such as b+ tree : Summarize briefly how to make use of indexes such as B+ tree or a hash indexes in selection, projection, and join operations?

Sketch the base-five pieces and each of the subtraction mode : Sketch the base-five pieces and each of the subtraction models to determine the following differences. Record sketches of your work and record the base-five numeral for each difference.

What is the maximum safe diving depth : A scuba diver can withstand pressures up to 4.2 atm without rish of getting the bends. What is the maximum safe diving depth

User Account

All Pages

List whether the index matches the given selection condition

Reference no: EM13336567

Reference no: EM13336567

Questions Cloud

Reviews

Write a Review

Database Management System Questions & Answers

Knowledge and data warehousing

Design a database schema

Entity-relationship diagram

Implement a database of courses and students for a school

Prepare the e-r diagram for the movie database

Design relation schemas for the entire database

Prepare the relational schema for database

Data modeling and normalization

Use cases perform a requirements analysis for the case study

Knowledge and data warehousing

Stack and queue data structure

Practice on topic of normalization

Assured A++ Grade

Academics

Major Subjects

Majors

Get In Touch

TERMS & POLICIES

HELP & SUPPORT