Software failures-database recovery and security, Database Management System

Software failures:  In such cases, a software error abruptly stops the implementation of the current transaction (or all transactions), therefore leading to losing the state of program implementation and the contents / state of the buffers.  But what is a buffer? A buffer is the portion of RAM that kept the partial contents of database that is currently needed by the transaction. The software failures can further be subdivided as:

a)   Application or Statement program failure

b)   DBMS software failure

c)   Failure due to viruses

d)   Operating system failure

A Statement of program may cause abnormal termination if it does not implement totally.  This happens if during the implementation of a statement, an integrity constraint gets desecrated. This leads to irregular termination of the transaction because of which any prior updates made by the transaction may still get reflected in the database going it in an inconsistent state.

A failure of transaction can happen if some code in a transaction program leads to its abnormal termination. For instance, a transaction can go into an infinite loop.

In such a case the only technique to break the loop is to abort the program.  Likewise, the failure can be traced to the DBMS or operating system and transactions are aborted abruptly. Therefore part of the transaction that was implemented before abort may cause some updates in database, and therefore the database is updated only partially which leads to an inconsistent state of database.

Posted Date: 3/12/2013 3:33:26 AM | Location : United States







Related Discussions:- Software failures-database recovery and security, Assignment Help, Ask Question on Software failures-database recovery and security, Get Answer, Expert's Help, Software failures-database recovery and security Discussions

Write discussion on Software failures-database recovery and security
Your posts are moderated
Related Questions
Project Description: I would like to get a database of a website which has clients email name and phone number. If you are able to get information from a website, by entering

management information system based on functional organisation

employee(empid,empname,dept,telno,mobno, add,sssno,tinno,WEdates,WEcomp,WEadd,WEpos,WEres) this is a employee record which is need to be normalize.the WE means work experience

Express types of information available in MySQL? Information as regards the result of queries:  This includes number of records affected by any SELECT or UPDATE or DELETE st

What is meant by heuristic optimisation?  Discuss the main heuristics that are applied during query optimisation.  Ans:  In heuristic optimization, heuristics are employed to r

Advantages of Observation  Methods: Bailey has pointed  out four  advantages of observation: 1. Superior in Data  Collection  on Non Verbal Behavior: When  a person  a opi

Explain the concept of QBE? Query-by-example represents a visual/graphical approach for accessing information in a database by the use of query templates called as skeleton tab

Optimistic Concurrency Control Is locking the only way to stop concurrency related problems? There exist some other ways too. One such way is known as an Optimistic Concurrency

How Relational Calculus is different from Relational Algebra? What do understand by TRC queries and DRC queries?  Ans: Relational calculus contain two calculi, the tuple relati

Fragmentation: It is definite as partitioning of a relation into various fragments.Every fragment can be stored at a dissimilar site.