Increased overheads on update: On the drawbacks side, it will need the system to ensure that all replicas of a relation are consistent. This shows that all the replicas of the relation require to be updated at the similar time, resulting in increased overheads. For instance, in a banking system, if account information is replicated at several sites, it is essential that the balance in a particular account should be the similar at all sites.

The problem of controlling concurrent updates by various transactions to replicated data is more difficult than the centralised approach of concurrency control. The management of replicas of relation can be simplified by deciding one of the replicas as the primary copy. For instance, in a banking system, the primary copy of an account may be the site at which the account has been opened. Likewise, in an airline reservation system, the primary copy of the flight may be related with the site at which the flight originates.

Posted Date: 3/13/2013 8:30:46 AM | Location : United States

Ask an Expert

Related Discussions:- Increased overheads on update-data replication, Assignment Help, Ask Question on Increased overheads on update-data replication, Get Answer, Expert's Help, Increased overheads on update-data replication Discussions

Write discussion on Increased overheads on update-data replication
Your posts are moderated

Write your message here..

Related Questions

Production management, create an er diagram for production management in fi... create an er diagram for production management in film industry

What are stored and derived attributes, What are stored and derived attribu... What are stored and derived attributes? Stored attributes: The attributes keeps in a data base are known as stored attributes. Derived attributes: The attributes that are de

ER diagram, #question. acompani datdbase needs to store information about e... #question. acompani datdbase needs to store information about employees (identified by a social security number,with salary and phone as attributes) and departments (identified by

DML complier, definition and its work definition and its work

Describe the static hash file with buckets and chaining, Describe the stati... Describe the static hash file with buckets and chaining and show how insertion, deletion and modification of a record can be performed. In static hash file organization, the wo

Write a program within embedded sql to associative relation, Write a progra... Write a program within embedded SQL to associative the total trip expenses of the salesman named ‘John' for the relations. EXEC SQL BEGIN DECLARE SECTION; long total_expenses;

What is storage manager, What is storage manager?  A  storage  manager ... What is storage manager?  A  storage  manager  is  a  program  module  that  gives  the  interface  between the Low level data  kept in a database and the application programs

Process of implementing system design in dynamic models, Process of impleme... Process of implementing system design in dynamic models There are three essential approaches to implementing system design in dynamic models. These approaches are as below:

Describe interfaces for the dba, Describe Interfaces for the DBA? Inte... Describe Interfaces for the DBA? Interfaces for the DBA - Most database systems holds privileged commands which could be used only through the DBA's staff. These involves com

What are the three types of data sources, What are the three types of data ... What are the three types of data sources used with ODBC? An ODBC file data source is a file that can be shared between database users. An ODBC system data source is one that is