What is index, Database Management System

Assignment Help:

What is Index?

An index is a physical structure having pointers to the data. Indices are created in an existing table to locate rows more quickly and efficiently. It is possible to create an index on one or more columns of a table, and each index is given a name. The users cannot see the indexes; they are just used to speed up queries. Effective indexes are one of the best ways to improve performance in a database application. A table scan occurs when there is no index available to help a query. In a table scan SQL Server examines every row in the table to satisfy the query results. Table scans are sometimes unavoidable, but on large tables, scans have a terrific impact on performance.

 


Related Discussions:- What is index

Transaction, what are the states of transaction?

what are the states of transaction?

Construct substantial data model, PART MARKING:  We will only mark TWO of t...

PART MARKING:  We will only mark TWO of the four questions below but you must submit answers to all four. We will choose the questions we mark randomly and we will supply you with

School portal design and development, Project Description: This is going...

Project Description: This is going to be a School portal to handle each activities in school such as, School fees payment, online registration and every other payment, course re

Differences between a file processing system and a dbms, List any two signi...

List any two significant differences between a file processing system and a DBMS. File Processing System vs. DBMS Data Independence - Data independence is the capacity t

Explain the term - handling boundary condition, Explain the term - Handling...

Explain the term - Handling Boundary Condition These are some circumstances that to be handled in any system initialization and termination. Describes how system is bro

Operator precedence-data manipulation language, Operator Precedence The...

Operator Precedence The basic operators used in SQL are * /   - + Operators of the similar priority are evaluated From Left to right Parentheses are used to force priorit

Define integrity, (a) Explain briefly the three parts of a relational Model...

(a) Explain briefly the three parts of a relational Model. (b) Contrast the following terms with an appropriate example: (i) stored attribute v/s derived attribute (ii) en

Describe participation constraints, Describe Participation Constraints? ...

Describe Participation Constraints? Participation Constraints - The participation constraint exacts whether the existence of an entity depends on its being related to another

Describe the terms ‘database'' and ‘data warehouse'', Problem: ‘Users a...

Problem: ‘Users and Information system specialists need to spend inordinate amounts of time locating and gathering data' (Watson and Hal, 1998) Recent developments in the ar

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