Concurrent transactions-backup and recovery, Database Management System

Assignment Help:

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 a variety of relationships between the data as well as to update and retrieve related data simply and efficiently.

Improved Security

Data is essential to any organisation and also confidential. In a shared system the multiple users share the data, all information has not been shared by all users. For instance, the salary of the employees has not been visible to anyone other than the department dealing in this. Therefore, database should be protected from unauthorised users. This is done by Database Administrator (DBA) by giving the usernames and passwords only to authorised users as well as granting privileges or the type of operation allowed. This is complete by using security and authorisation subsystem. Only authorised clients may use the database and their access types can be restricted to only retrieval, update, insert or delete or any of these. Let us take example; the Branch Manager of any company may have access to all data while the Sales Assistant may not have access to salary details.

Improved Backup and Recovery

A file-based system may fail to give measures to protect data from system failures. This lies only on the user by taking backups intermittently. DBMS gives facilities for recovering the hardware and software failures. A recovery and backup subsystem is liable for this. In case a program fails, it restores the database to a state in which it was before the implementation of the program.

Support for concurrent transactions

A transaction is defined as the unit of work. For illustration, a bank may be there in a transaction where an amount of Rs.5000/- is transmitted from account X to account Y. A DBMS also transmit multiple transactions to occur concurrently.


Related Discussions:- Concurrent transactions-backup and recovery

Demonstrate the uml model, Demonstrate the UML model Using UML, it is p...

Demonstrate the UML model Using UML, it is possible to generate code in any of the programming language from UML model (called forward engineering) and rebuild a model from an

What are advantages of using an index and disadvantages, What are the advan...

What are the advantages of by using an index and what are its disadvantages ? In difference, if the search key of a secondary index is not a candidate key, it is not sufficient

Consistency, what do you mean by consistency in rdbms?

what do you mean by consistency in rdbms?

find a non-redundant cover and canonical cove, Given the following set of ...

Given the following set of functional dependencies {cf→ bg, g → d, cdg → f, b → de, d → c} defined on R(b,c,d,e,f,g) a. Is cf→ e implied by the FDs? b. Is dg a superkey?

Search the name department number and salary of employees , Example : Searc...

Example : Search the name, department number and salary of employees drawing minimum salary in that department. SELECT ENAME, SAL, DEPTNO  FROM EMP WHERE SAL IN (SELECT MI

Central database schema, Consider an information system designed for an onl...

Consider an information system designed for an online company which provides IT products and services. These include desktops, laptops, networking products, IT books, parts, and te

Design and prototype, This assignment is worth 45% of your final grade for ...

This assignment is worth 45% of your final grade for this module.  Marks will be awarded as follows: Prototypes (wireframe and web based prototype) You are expected

Briefly explain the state diagram by taking one example, Briefly explain th...

Briefly explain the state diagram by taking one example. State Diagram - An object can be given a sequence of input instructions. The state of the object can vary depending u

Creating views with read only option-data control, Creating views with Read...

Creating views with Read only option : In the view definition this option is used to make sure that no DML operations can be done on the view.

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