Describe JDBC Architecture in brief.- The JDBC API supports both two-tier and three-tier processing models for database access.
- In this a Java application talks directly to the data source.
- It requires a JDBC driver which communicates with the particular data source being accessed.
- A user's commands are delivered to the database or other data source, and the results of those statements are sent back to the user.
- The data source may be located on another machine to which the user is connected via a network.
- This is referred to as a client/server configuration, with the user's machine as the client, and the machine housing the data source as the server.
- The network can be an intranet, which, for example, connects employees within a corporation, or it can be the Internet.
- In this the commands are sent to a "middle tier" of services, which then sends the commands to the data source.
- The data source processes the commands and sends the results back to the middle tier, which then sends them to the user.
- MIS directors find the three-tier model very attractive because the middle tier makes it possible to maintain control over access and the kinds of updates that can be made to corporate data.
- Another advantage is that it simplifies the deployment of applications.
- Finally, in many cases, the three-tier architecture can provide performance advantages.