Connect to a Database

import java.sql.*;

public class jdbcConn

   public static void main(String[] args)

try

         Class.forName("org.apache.derby.jdbc.ClientDriver");

      catch(ClassNotFoundException e)

         System.out.println("Class not found "+ e);

      System.out.println("Jdbc Class found");

      int no_of_rows = 0;

try

         Connection con = DriverManager.getConnection

         ("jdbc:derby://localhost:1527/testDb","username","password");

         Statement stmt = con.createStatement();

         ResultSet rs = stmt.executeQuery("Select * from employee");

         while (rs.next())

            no_of_rows++;

       System.out.println("There are "+ no_of_rows + " record in the table");

      catch(SQLException e)

         System.out.println("SQL exception occured" + e);

Edit Table

import java.sql.*;

public class jdbcConn

   public static void main(String[] args) throws Exception

      Class.forName("org.apache.derby.jdbc.ClientDriver");

      Connection con = DriverManager.getConnection

      ("jdbc:derby://localhost:1527/testDb","username","password");

      Statement stmt = con.createStatement();

      String query ="create table employees  (id integer    primary key, first_name char(50),last_name char(75))";

      stmt.execute(query);

      System.out.println("Employee table created");

      String query1 = "alter table employees add

      address Char(100) ";

      String query2 = "alter table employees drop

      column last_name";

      stmt.execute(query1);

      stmt.execute(query2);

      System.out.println("Address column added to the table

      & last_name column removed from the table");

      String query3 = "drop table employees";

      stmt.execute(query3);

      System.out.println("Employees table removed");