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Select Data Base

This chapter provides an example on how to select a Database using JDBC application. Before executing the following example, make sure you have the following in place:
  • To execute the following example you need to replace the username and password with your actual user name and password.
  • Your MySQL or whatever database you are using, is up and running.
Required Steps

The following steps are required to create a new Database using JDBC application:
  • Import the packages: Requires that you include the packages containing the JDBC classes needed for the database programming. Most often, using import java.sql.* will suffice.
  • Register the JDBC driver: Requires that you initialize a driver so you can open a communications channel with the database.
  • Open a connection: Requires using the DriverManager.getConnection() method to create a Connection object, which represents a physical connection with a selected database.
  • Selection of database is made while you prepare database URL. Following example would make connection with STUDENTS database.
  • Clean up the environment: Requires explicitly closing all the database resources versus relying on the JVM's garbage collection.
Sample Code

Copy and past the following example in, compile and run as follows:

//STEP 1. Import required packages
import java.sql.*;
public class JDBCExample {
// JDBC driver name and database URL
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost/STUDENTS";
// Database credentials
static final String USER = "username";
static final String PASS = "password";
public static void main(String[] args) {
Connection conn = null;
//STEP 2: Register JDBC driver
//STEP 3: Open a connection
System.out.println("Connecting to a selected database...");
conn = DriverManager.getConnection(DB_URL, USER, PASS);
System.out.println("Connected database successfully...");
}catch(SQLException se){
//Handle errors for JDBC
}catch(Exception e){
//Handle errors for Class.forName
//finally block used to close resources
}catch(SQLException se){
}//end finally try
}//end try
}//end main
}//end JDBCExample

Now, let us compile the above example as follows:


When you run JDBCExample, it produces the following result:

C:\>java JDBCExample
Connecting to a selected database...
Connected database successfully...
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