Intro to DBMS

DBMS Architecture

The DBMS design depends upon its architecture. So, DBMS architecture depends upon how users can connect to the database to meet their requirements.

In DBMS architecture, there is an interface (APIs like ODBC and JDBC) at the client end, which is used to access the database. This interface uses the query in any language (PHP, Jave, etc.) to select or fetch the record from the database.

Types of DBMS Architecture

There are three major types of DBMS Architecture

database architecture types

i. 1-Tier Architecture

  • 1-tier architecture is the simplest architecture where the Client, Server, and Database all reside on the same machine. So, anytime you install a database on your machine, you can access it through SQL queries. Therefore, This type of architecture is an example of 1-tier architecture.

  • In simple words, in 1-tier architecture, the user can directly sit on the DBMS and use it.

  • 1-tier architecture is rarely used in production. It is used where a quick response is required. For example, the development of the local application

1-tier architecture

II.  2-tier architecture

  • In the two-tier architecture, applications on the client side(i.e., PC, Mobile, Tablet, etc.) can directly communicate with the database (server side).

  • User interfaces (APIs like ODBC and JDBC) and application programs are run on the client side to establish a connection with the server.

2-tier architecture
  • The database server is responsible for query processing and transaction management.

An example of a 2-tier Architecture is a CMS (Contact Management System). CMS can made through MS- Access.

Real Life Example

When any person Goes to the bank or railway station, fill out a manual application form for ticket reservation or bank transactions. These forms are given to some operators. Operators are using the client’s machines behind the window. Then, the client’s machines access the database to verify details. So, this is an example of 2-tier architecture.


Advantages of 2-Tier architecture 

  • It is easy to use and maintain because it has limited clients.

Disadvantages of 2-Tier architecture 

  • However, the problem with this architecture is scalability. Scalability means when the number of users increases, then two-tier architecture does not work properly.

  • Security is another main problem because it does not allow role-based access. It means an author can work as an administrator because every client has direct and similar access to the database.

  • The traffic load on the database server is high because it first processes the query and then provides the required data as well.

III. 3-tier architecture

  • In a 3-tier architecture, the client cannot directly communicate with the database server. It contains another layer (application layer) between the client and server.

  • The user on the client end interacts with an application server (also called the business layer), which further communicates with the database system.

  • The end-user has no idea about the database, and the database also has no idea about any end user.

  • The 3-tier architecture is mostly used in web applications.

3-tier architecture

Advantages of 3-tier architecture

  • High security because of role-based architecture.

  • Highly flexibility (scalability)

Disadvantages of 3-tier architecture

  • Tough to maintain as compared to 2-tier architecture