What is magnetic disks, Database Management System

Assignment Help:

What is magnetic disks?explain it?

Magnetic disk provides the bulk of secondary storage of modern computer system. The disk capacity is growing at over 50% per year. But the storage needs of large applications have also been growing very fast and in some case each faster than the growth rate of disk capacities. A large data base may need 100 of disks.

Physical characteristics of disk

Physical disks are relatively simple. Every disc platter has a flat circular shape

We can call magnetic disk as

Ø   hard disk

Ø   Floppy disk

The read write head keeps information on a sector magnetically as reversals of the direction of magnetization of the magnetic material. There might be hundreds of concentric tracks on a disc surface, having thousands of sectors.

 


Related Discussions:- What is magnetic disks

Concurrent transactions-backup and recovery, Representing complex relations...

Representing complex relationship among data A database may contain varieties of data interrelated to each other in numerous ways. A DBMS must have the capability to represent

Which operator is used to compare a value to a list literals, Which operato...

Which operator is used to compare a value to a list of literals values that have been specified? BETWEEN operator is used to compare a value to a list of literals values that h

Define partial, Partial Key : It is a group of attributes that can uniquel...

Partial Key : It is a group of attributes that can uniquely identify small entities and that are related to same base entity. It is sometime named as Discriminator.  Altern

Explain recursive relationship type, Explain Recursive relationship type? ...

Explain Recursive relationship type? Recursive relationship type: A recursive relationship is one in that the similar entity participates more than once in the relationship

What is a disjoint less constraint, What is a disjoint less constraint? ...

What is a disjoint less constraint? Ans: It needs that an entity belongs to no much more than one level entity set.  Disjoint less constraint needs that an entity belongs to

What is a heterogeneous distributed database, What is a heterogeneous distr...

What is a heterogeneous distributed database? In a heterogeneous distributed database, dissimilar sites may use different schemas, and dissimilar dbms s/w. The sites may not be

Explain the need for the bcnf normal form, Surgeons identified by doctor ID...

Surgeons identified by doctor ID (DOCID) operate on patients identified by patient ID (PATID) in operating theaters identified by room numbers (ROOMNO). Each surgeon can operate on

Write short note on data models, Write short note on Data models? Data...

Write short note on Data models? Data models: A data model is an abstract model which elaborates how data is represented and accessed. The term data model has two commonly ac

What is primary key, What is Primary key? Primary Key - Primary key i...

What is Primary key? Primary Key - Primary key is one of the candidate keys which uniquely identifies each row in the relation.

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