What is primary index, Database Management System

Assignment Help:

Primary Index

In primary index, there is a one-to-one relationship among the entries in the index table and the records in the major table. Primary index can be of two types:

Dense primary index: the number of entries in the index table is the similar as the number of entries in the major table. In other words, each and every record in the major table has an entry in the index.

Sparse or Non-Dense Primary Index:

For large tables the Dense Primary Index itself starts to grow in size. To keep the size of the index smaller, instead of pointing to each and every record in the major table, the index points to the records in the main table in a gap.

 


Related Discussions:- What is primary index

Explain domain-oriented relational calculus?, How does Tuple-oriented relat...

How does Tuple-oriented relational calculus vary from domain-oriented relational calculus? The tuple-oriented calculus uses a tuple variables i.e., variable whose only allowed

What are uncommitted modifications, What are uncommitted modifications? ...

What are uncommitted modifications? The immediate-modification technique permits database modifications to be output to the database whereas the transaction is still in the act

What is a recovery scheme, What is a recovery scheme? An integral part ...

What is a recovery scheme? An integral part of a database system is a recovery scheme that can restore the database to the reliable state that existed before the failure.

Create a entity-relationship diagrams, This project requires you to create ...

This project requires you to create a database design.  Your design will be documented in a set of Entity-Relationship diagrams.  Draw a set of Entity-Relationship diagrams to mode

A file manipulation command that extracts some records, A file manipulation...

A file manipulation command that extracts some of the records from a file is called ? A file manipulation command that extracts some of the records from a file is called SELECT

The need for three level architecture, The need for three level architectur...

The need for three level architecture The aim of the three level architecture is to divide each user's view of the database from the way the database is physically shown.

What is explicit update, What is Explicit update In explicit update,...

What is Explicit update In explicit update, each derived attribute is defined with respect to one, or more fundamental base object(s). The object designer determines that de

What is a block and a block number, What is a block and a block number? ...

What is a block and a block number? A block is a contiguous sequence of sectors from a single track of one platter. Every request specifies the address on the disk to be refere

Functional Dependencies, What exactly is the concept of Functional Dependen...

What exactly is the concept of Functional Dependencies? And how do we associate this concept with the logic of Super-keys, Candidate Keys, etc? Given Relation R(A,B,C,D,E) with de

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