Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Failures and Recovery
In practice various things might occur to prevent a transaction from completing. Recovery methods are used to bring database, which does not satisfy consistency needs, into a consistent state. If a transaction finishes normally and commits then all the alters made by the transaction on the database are permanently registered in the database. They should not be lost. But, if a transaction does not finish normally and terminates abnormally then all the changes made by it should be discarded. An abnormal termination of a transaction may be because of various causes, including:
a) User may decide to terminate the transaction issued by him/ her
b) There may be a deadlock in the system
c) There may be a system failure.
The recovery mechanisms must make sure that a consistent state of database can be restored under all circumstances. In case of transaction terminate or deadlock, the system remains in control and can deal with the failure but in case of a system failure the system loses control because the computer itself has failed. Will the results of such type of failure be catastrophic? A database has a vast amount of useful information and any system failure should be recognised on the restart of the system. The DBMS should recover from some such failures.
Describe the algorithm to draw the dependency graph? Ans: Algorithm to draw Precedence Graph is like this: a. For every transaction T i participating in schedule S, make
Advantages of Data Distribution The primary benefit of distributed database systems is the ability to access and share data in a reliable and efficient manner.
define anomalies and different types of anomalies with example
Why is database design important?
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4
Conversion of entity sets: I) For every strong entity type E in the ER diagram, we make a relation R containing all the easy attributes of E. The relation R pri
What is relational model feature? A relational model feature is much more data independence than some other database models.
what are the purposes of dbms in details
Draw the database using the ER approach and then make the tables accordingly. Populate the tables so that every table have at least 10 tuples. Then using Java and SQL, execute the
Views in relational algebra: 1. Basic expression contains either a) A relation in the database. b) A constant relation. 2. General expressions are madde out of sma
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd