Sparse and dense indexes, Database Management System

Assignment Help:

Sparse and Dense Indexes

These indexes in principle are the similar as that of indexes used at the back of the book. The key facts of the indexes are:

  • They are arranged on the order of the index value (ascending or descending) as per the option of the creator.
  • The indexes are logically individual files (just like individual index pages of the book).
  • An index is firstly formed for fast access of information.
  • The primary index is the index on the ordering field of the data file while a secondary index is the index on any other field, therefore, more useful.

 But what are dense and sparse indexes?

 Sparse indices are the indices that do not contain all the available values of a field. An index sets the records as per the index values. A sparse index is where the size of the group is one or more, whereas in a dense index the size of the group is 1. In other words a dense index have one index entry for each value of the indexing attributes, while a sparse index also known as non-dense index have few index entires out of the available indexing attribute values. For instance, the primary index on enrolment number is sparse, whereas secondary index on student name is dense.

 

 


Related Discussions:- Sparse and dense indexes

MYSQL, write an SQL statement to create the database in MYSQL server

write an SQL statement to create the database in MYSQL server

What is trigger, What is trigger?  Triggers are statements that are exe...

What is trigger?  Triggers are statements that are executed automatically by the system as the side effect of a modification to the database.

Need customer management program, Project Description: This is a Custome...

Project Description: This is a Customer Management project. Customer data is presented in a text file. The program can load this text data into its database columns. The data ma

What are the different approaches for database design, What are the differe...

What are the different approaches for database design? There are two basic approaches for database design which are as follows: Attribute driven: It compiles a list of att

Draw and explain the three level architecture of database, Draw and explain...

Draw and explain the three level architecture of the database system? A DBMS gives three levels of data is said to follow three-level architecture. The trget of the three-schem

Sql insert statements, Submit SQL INSERT Statements that will populate the ...

Submit SQL INSERT Statements that will populate the database with sample data.  You must insert at least 5 records into each table in your database.Submit your SQL INSERT Statement

Entity Relationship for music band managem modeliing, i am required to come...

i am required to come up with entities relationships, optionality and cardinality from a scenario. there is a night club and bookings for a musician band

Why does a dbms query language is designed, Why does a DBMS query language ...

Why does a DBMS query language is designed? A DBMS query language is designed to support end users who use English-like commands. support in the development of complex applicat

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