Retrieving Data - a Simple JDBC Example

There are some distinct steps in accessing a database using JDBC.

STEP 1: Make a connection

This Step involves the driver setup and loading. Hence it is dependent on the type of driver you are using. To make a connection with the Database, we first

• Load the driver
• Get a connection using this driver

Load The driver

If you are using the Sun JDBC-ODBC bridge :

Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

If you are using any other driver please refer to Appendix A for a sample code for loading Oracle driver. The code for loading any other JDBS driver will be similar.

The forName Method will create an instance of a driver and register it with the DriverManager.

Get a connection using this driver

The Generic code is:

Connection con = DriverManager.getConnection(url,
                     "myLogin", "myPassword");

url: If you are using JDBC-ODBC bridge then url will look like:

String url = jdbc:odbc:myDriver

Where myDriver is the Data Source Name of the ODBC driver to connect to your database.

If you are using any other driver please refer to Appendix A for an example of how "url" will look.

The Connection returned (con) in the previous example is an 'open' connection which we can use to send SQL data over.

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STEP 2: Use This Connection to Access the Database