Before moving to database types, let’s look at what is a database, the database is an organized way of managing information’s, which can be easily created by users, access and updated by users. The database has three types.

• Centralized database
• Decentralized database
• Distributed database

Each type of database has it’s own advantage and disadvantages according to its nature and our need we use them.

Centralized database

It’s contains complete information on a single database in a center location.

Pros

• Centralize database are easier to setup
• Easy to maintain
• Data integrity
• Easy to generate report for analysis.

Cons

• Bottlenecks can occur as a result of high traffic.
• Security issues.
• Hard to scale
• Single point of failure.

Decentralized database

Data will not store into a single database, Data distributed into different databases and servers. which communicate between each others with the help of different protocols.

Pros

• High performance
• Easly scalable
• Distributed data processing
• Highly stable
• In case of one system malufunction,other systems are able to function

Cons

• Hard to setup
• High maintenance cost
• Difficult to maintain integrity
• Complex to design a database
• Reporting and analysis on decentralized database is costly

Distributed Database

Data is distributed between more then one system which are interconnected with each other It’s represented as a peer-to-peer network. where every node/system has some and all of the data, where data is store in every node. Dedicate repositro is not required as a source of data. Air traffic control is a good examle of Distributed database where the trafic information is store every node. and each node has equal right in the network.

In a homogenous distributed database all databases are same. In heterogeneous distributed database system database are diffrent.

Pros

• Most eficiant type of database system in the point of securty and stablity
• High redundancy
• Comparatively high response rate
• Transparency

Cons

• Difficult to setup.
• Multiple point of failure, Difficult to maintain
• Complex setup and it is difficult to make sure that user gets uniform view of database.
• The distributed database is complicated and it is difficult to find people with the necessary experience who can manage and maintain it.