Describe log based recovery, Database Management System

Assignment Help:

Describe log based recovery

The most usably structure for recording data base modification is the LOG the log is a sequence of log records recording all the update activities in the data base. There are several types of log records. An update log records describes a single data base write it has these fields

Transaction identifier

Data item identifier

Old value

New value

The various types log records as.

  • < Ti start >. Transaction Ti has started
  • < Ti , Tx v1,v2 > .Transaction Ti has performed a right on data item
  • < Ti commit > Transaction Ti has committed
  • < Ti about > Transaction Ti has aborted

Ø  Deferred data base modification

Ø  Immediate data base modification

Ø  Check point

Ø  Shadow paging

 


Related Discussions:- Describe log based recovery

Assignment SQL Management Server 2012, Have database built but having probl...

Have database built but having problems with some questions that go with the database

Basics of relational models, In the first unit of this block, you have been...

In the first unit of this block, you have been given with the details of the Database Management System, its structure, advantages etc. This unit is an attempt to give you informat

Create a e-r diagram or uml class diagram, We require an advanced system fo...

We require an advanced system for a Sports Centre, you are concerned only with representing the data discussed below about bookings and members. (The complete system may contain ot

Write a query to find name from the relational algebra, Consider the relati...

Consider the relations City (city_name, state) Hotel (name, address) City_hotel (hotel_name, city_name, owner) Answer the following queries in relational algebra (i) Find

What is theta join explain, What is theta join explain? Theta  Join  -...

What is theta join explain? Theta  Join  - The  theta  join  operation  is  an  extension  to  the  natural-join operation which permits us to merge selection and a Cartesian

DBMS, give some example real life situation where DBMS are most suitable

give some example real life situation where DBMS are most suitable

What is a data dictionary, What is a data dictionary?  A data dictionar...

What is a data dictionary?  A data dictionary is a data structure which keeps Meta data about the structure of the database i.e.  the schema of the database.

Determine the minimal set of functional dependencies, Determine the minimal...

Determine the minimal set of functional dependencies for the following data. This table is part of the OHSU database of extracurricular activities and tracks the DMICE band's co

Define and differentiate among ordered indexing and hashing, Define and dif...

Define and differentiate between ordered indexing and hashing. Ans: Ordered indexing: To gain fast random access to records in a file, we can make of an index structure. Every

Data fragmentation-use of partial data by applications, Use of partial data...

Use of partial data by applications : In common, applications work with views rather than whole relations. Thus, it may be more appropriate to work with subsets of relations rather

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