Introduction to JDBC

Introduction to JDBC 

What is JDBC API?

JDBC API provides ways for Java applications to communicate with databases.

JDBC Architecture

• Java application that needs to communicate with database has to be programmed with JDBC API.
• The DriverManager class defines objects which can connect Java applications to a JDBC driver
• JDBC driver will support Data source like oracle, mySQL and SQl.

Two Tier Architecture

• A Java application / Applet will directly communicate with data source.
• 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.

 Three Tier Architecture

• In the three-tier model, 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. 
• The data source may be located on another machine to which the user is connected via a network. 

• Advantages 
• Middle tier has control over access and updates. 
• Simplifies deployment 
• Performance advantages