Here is an example that retrieve the integer values from the database and stored in the integer variables. In addition to it, we have added numbers that are retrieved from the database. The sum of numbers is then saved to another table.

import java.sql.*;

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

        Class.forName("com.mysql.jdbc.Driver").newInstance();
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root" );
        Statement st=conn.createStatement();
        ResultSet rs=st.executeQuery("select * from numbers");
        Statement stmt=conn.createStatement();
        while(rs.next()){
            int num1=rs.getInt("number1");
            int num2=rs.getInt("number2");
            int sum=num1+num2;

            System.out.println(num1+" +\t "+num2+" =\t "+sum);
                        int i=stmt.executeUpdate("insert into result(result) values("+sum+")");


        }
    }
}