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

Implementing a data mining algorithm, i need to implememnt a treee based mi...

i need to implememnt a treee based mining algorithm. do you have an expert that can do that?

List some security violations, List some security violations (or) name any ...

List some security violations (or) name any forms of malicious access. A) Unauthorized reading of data B) Unauthorized modification of data C) Unauthorized destruction of

Set concept is used in which type of modelling, SET concept is used in whic...

SET concept is used in which type of modelling? SET concept is used in Network Model.

What is primary key explain, What is primary Key Explain? Primary Key ...

What is primary Key Explain? Primary Key - Primary key is one of the candidate keys. It should be selected such in which its attribute values are never, or very rarely, chang

Prepare a site map and submit it in bing and google, Project Description: ...

Project Description: I am updating my Javascript + HTML website with five domains for the same website I would like to know if I want to create site map and submit it in all the

Example-revoke all on emp from mca12, Example:  //REVOKE ALL ON EMP FROM MC...

Example:  //REVOKE ALL ON EMP FROM MCA12;                              (All permissions will be cancelled) You can also cancel only some of the permissions. Drop: A user-

Example of database optimisation, Create 1 experiment to demonstrate an asp...

Create 1 experiment to demonstrate an aspect of query optimisation by using access-path structures (indexes), decomposition, or denormalisation. Once satisfied with your experiment

Describe the storage structure of indexed sequential file, Describe the sto...

Describe the storage structure of indexed sequential files and their access method. Ans: Index offers a lookup capability to rapidly reach the vicinity of the desired record.

Example database application, We will explain here an example database appl...

We will explain here an example database application having COLLEGE database and use it in showing several E-R modelling concepts. College database remains track of faculty, Stu

Differance between internal and external schema, Differance between interna...

Differance between internal and external schema? Internal and external schema: Internal Schema • Describes the physical storage structure • Uses a physical data model External

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