Increased overheads on update-data replication, Database Management System

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







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
Related Questions
Scenario 1: Power goes out after the first instruction. What happens?

Probelm: (a) A distributed database (DDB) is a collection of multiple, logically interrelated databases which are physically distributed over a computer network" (i) Give a

What is normalization? It is a method of analysing the given relation schemas based on their Functional Dependencies (FDs) and primary key to attain the properties (1).Minim

how to calculate frequency count of algorithm

Operator Precedence The basic operators used in SQL are * /   - + Operators of the similar priority are evaluated From Left to right Parentheses are used to force priorit

What is a primary key? Primary key is chosen by the database designer as the principal means of identifying an entity in the entity set.

What is DML compiler? DML Compiler: Translates DML statements in a query language within low level instructions understandable through the query evaluation engine. Attempts to

#Use the following database schema: 1) Patient—PatientID, Name, DOB 2) Doctor—DoctorID, Name, MedLicenseNumber, Phone 3) Medication—MedicationID, BrandName, GenericName 4) Prescrip

What is document scanning and imaging? Document scanning and imaging, or digital archiving, is the method of scanning a document into a digital image to archive and retrieve a

Define union compatibility? Explain why INTERSECTION of two relations cannot be performed if they are not union compatible? Two relations R(A1, A2,-------, An) and S(B1, B2,--