Implementación de la vista materializada a través del programa Java

// Java Program to implementat
// Materialized view
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Scanner;
import java.sql.PreparedStatement;
  
public class Materialised_View {
    public static void main(String[] args)
    {
        // Declare connection and resultset objects
        Connection conn;
        ResultSet rs;
  
        // Declare statement objects
        Statement stmt, stmt1;
  
        // query to retrieve the details of student table
        String query = "select * from student;";
        Scanner sc = new Scanner(System.in);
        System.out.println("Student Table is Created as Follows:\n");
        System.out.println
              ("*******Student*********\nsid\tsname\taddress\n---- ");
        try {
  
            // Register the mysql driver
            DriverManager.registerDriver(new com.mysql.jdbc.Driver());
  
            // get the connection
            conn = DriverManager.getConnection
             ("jdbc:mysql:// localhost:3306/adbms_practicals", "root", "kernel");
  
            // Initialize the statement object
            stmt = conn.createStatement();
  
            // execute the query and store the result
            rs = stmt.executeQuery("select * from student;");
  
            while (rs.next()) {
                // Iterate through the result set and display
                // content of each row of student table.
                System.out.println(rs.getString(1) + "\t" 
                   + rs.getString(2) + "\t" + rs.getString(3));
            }
  
            System.out.println("\n\nView of this Student Table is As Follows:");
            rs = stmt.executeQuery("select * from Student_Data2;");
            System.out.println
             ("\n***********Student View*******\nsid\tsname\taddress\n-------");
            while (rs.next()) {
                // Iterate through the result set and display
                // content of view of student table.
                System.out.println(rs.getString(1) + "\t" 
                  + rs.getString(2) + "\t" + rs.getString(3));
            }
            while (true) {
  
                // Perform the operations on table
                System.out.println("Menu:\n1.Insert\n2.Delete\n3.
                 See Changes in View Student_Data2\n4.Exit\nEnter Choice:");
  
                // take the input from user to insert / delete / see changes
                int ch = sc.nextInt(); 
  
                int sid;
                String sname = "";
                String address = "";
                switch (ch) {
                case 1:
                    System.out.println("Enter sid:");
                    sid = sc.nextInt();
  
                    System.out.println("Enter sname:");
                    sname = sc.nextLine();
  
                    System.out.println("Enter address:");
                    address = sc.nextLine();
  
                    // create the preparedStatement object and set the values
                    PreparedStatement st3 = conn.prepareStatement
                      ("insert into student values(?, ?, ?);");
  
                    st3.setInt(1, sid);
                    st3.setString(2, sname);
                    st3.setString(3, address);
                    st3.executeUpdate();
  
                    // create the preparedStatement object and set the values
                    PreparedStatement st1 = conn.prepareStatement
                        ("insert into Student_Data2 values(?, ?, ?);");
  
                    st1.setInt(1, sid);
                    st1.setString(2, sname);
                    st1.setString(3, address);
                    st1.executeUpdate(); // execute the preparedStatement to insert row
                    System.out.println("row inserted");
  
                    break;
  
                case 2:
                    System.out.println("Enter sid to be deleted:");
                    sid = sc.nextInt();
  
                    // create the preparedStatement object and set the values
                    PreparedStatement st4 = conn.prepareStatement
                      ("delete from Student_Data2 where sid=?;");
                    st4.setInt(1, sid);
  
                    PreparedStatement st2 = conn.prepareStatement
                        ("delete from student where sid=?");
                    st2.setInt(1, sid);
  
                    // execute the preparedStatement to delete row
                    st2.executeUpdate();
  
                    System.out.println("row deleted");
                    break;
  
                case 3:
                    System.out.println("\n\nChanges Done in the 
                     Student table also Affects the View Student_Data2");
  
                    rs = stmt.executeQuery("select * from Student_Data2;");
                    System.out.println
                      ("\n*****Student*******\nsid\tsname\taddress\n--------");
                    while (rs.next()) {
  
                        // Iterate through the result set and display
                        // recent changes of the table
                            // which got reflected in view.
                            System.out.println(rs.getString(1) + "\t" 
                            + rs.getString(2) + "\t" + rs.getString(3));
                    }
                    break;
  
                case 4:
                    System.exit(0); // User wants to exit
                    break;
                }
            }
        }
        catch (Exception e) { // catch all exceptions here.
            System.out.println(e);
        }
    }
}