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Week 10 Introduction to Distributed Database System

Distributed Data Independence

Distributed Transaction Atomicity

Recent Trends

Types of Distributed Databases

Distributed Database Architectures

Applications

Functions of a DDBMS

summary Real-life example quiz



A Typical example of concurrency control in real life would be:

A travel company that has many branches all over the world to sell tickets for different destinations. Each branch needs only to access its own data 90% of the time and only occasionally have a need to access remote data. The central office needs to have an up to date version of the data as well.With a single central database, all queries and updates have to travel across the network. This may cause a heavy load on the system. It also means if the central database breaks or the network goes down, the entire organiza-tion is affected.

A distributed database solves some of these issues.With a distributed database, the central database is updated over nights as a batch operation, but day-to-day work in the branches is carried out using the local portion of the database. If the network fails, then they can carry on as normal until it is fixed.

1. A database in which data is stored on several computers is called a A. client-server database B. network database C. concurrent database D. distributed database E. centralized database

2. Which is one of the types of distributed databases A. Binary B. Tertiary C. Shared data D. Homogeneous E. Centralized

3. A distributed databases can share memory A. True B. False


Enter answer,,,. 1. 2. 3.


1. A database in which data is stored on several computers is called a A. client-server database B. network database C. concurrent database D. distributed database E. centralized database

2. Which is one of the types of distributed databases A. Binary B. Tertiary C. Shared data D. Homogeneous E. Centralized

3. A distributed databases can share memory A. True B. False


Enter answer,,,. 1. D 2. D 3. A


4. A distributed databases cannot share disks. A. True B. False

5. Which is not a functionality of distributed databases? A. Extended communication services. B. Distributed query processing. C. Extended concurrency control. D. Faster compilation E. Extended recovery services.


answer is: 4. 5.


4. A distributed databases cannot share disks. A. True B. False

5. Which is not a functionality of distributed databases? A. Extended communication services. B. Distributed query processing. C. Extended concurrency control. D. Faster compilation E. Extended recovery services.


answer is: 4. B 5. D


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