Architecture of Database Management System
DBMS architecture helps in
development, implementation, design, and maintenance of a database that store
and organize information for agencies, businesses, and institutions. It is the base of any
database management system, which allows it to perform the functions effectively
and efficiently. The whole concept of DBMS depends upon its architecture. It
can be designed as centralized, decentralized, or hierarchical.
The database management system architecture can be seen as either a single-tier or multi-tier, but logically, it can be of two types: 2-tier architecture and 3- tier architecture.
In 1-tier architecture, the
database is directly available to the DBMS user for executing the SQL queries
and storing data in it. Any changes or updates that are done here will be
reflected directly to the database in the database management system.
Generally, 1-tier architecture is used for the development of applications where a programmer or developer directly communicates with the database for a quick response.
The 2-tier Architecture
of DBMS is based on a client-server machine. In this type of architecture,
applications on the client-side can interact directly with the database at the
server-side. For this interaction between client and the server, application
programming interface (API) like Open Database Connectivity (ODBC) and Java
Database Connectivity (JDBC).
This architecture gives poor performance when there are a large number of users at the client machine to access the database.
Examples of 2-tier architecture are Oracle, Sybase, Microsoft SQL Server, etc.
The DBMS 3-tier
architecture consists of another layer between the client and the server. In
this architecture, the client cannot directly interact with the server. Its
features, such as data backup, recovery, security, and concurrency control make
it the most commonly used architecture for designing the database management
The 3-tier architecture consists of the following layers:
- Presentation layer: This layer is also known as the client layer. It is the front end layer in the 3-tier architecture and consists of a user interface. The main purpose of this layer is to communicate with the application layer.
- Application layer: This layer is also known as the business logic layer. It acts as a middle layer between the client and the database server for exchange of partially processed data.
- Database layer: The data or information is stored in this layer. This layer contains a method to connect with the database and to perform operations such as insert, update, and delete.