Explain the JDBC Architecture - 2 tier and 3 tier both

Explain the JDBC Architecture - 2 tier and 3 tier both

JDBC APIs support both the architectures - 2-tier and 3-tier models for accessing a relational database.

JDBC for a 2-tier architecture

In such an architecture, the Java application (or Applet) communicates directly with the data source (or database). The database may reside on the same machine or may be on another machine to which the clinet machine needs to be connected through a network. In the latter case it will be a clinet-server configuration and the server will hold the database. The client will send the statements to the database residing on the server and the result will be communicated back to the client.

In this architecture, the client machine will typically be a Java application and the server machine will have a Relational Database installed on it.

JDBC for a 3-tier architecture

In such an architecture, the client machine will send the database access statements to the middleware, which will then send the statements to the database residing on the third tier of the archirecture, which is normally referred to as the back end. The statements will be processed there and the result be returned back to the client through the middle tier. This approach will have all the advantages associated with the 3-tier architecture, such as better maintainability, easier deployment, scalability, etc.

This scenario will typically have a Java Applet or a Web Browser as the clinet tier, an Application Server as the Middle-tier, and a Relational DBMS as the Back-end.