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import java.io.*;
import java.text.*;
import java.util.*;
import java.sql.*;

public class erotima3 {
    public static void main(String args[]){
        String url = "jdbc:sqlserver://altebaran.dmst.aueb.gr:1433;" +
                           "databaseName=DB32;user=G532;password=49bs95959;";
        Connection dbcon ;
        Statement stmt;
        ResultSet rs;
        int cr_number;
        int card_for_delete;
        int cust_code=0;
        System.out.println("Δώσε τον αριθμό της πιστωτικής κάρτας που θέλεις να διαγράψεις:");
        Scanner input = new Scanner(System.in);
        card_for_delete = input.nextInt();

        /* declare ODBC conectivity */
        try {Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");}
        catch(java.lang.ClassNotFoundException e)
        {System.out.print("ClassNotFoundException: ");
        System.out.println(e.getMessage());}
            /* execute SQL statements */
        try {
                dbcon = DriverManager.getConnection(url);
            stmt = dbcon.createStatement();
            rs = stmt.executeQuery("SELECT card_number, customer_code FROM credit_card");
            while (rs.next()) {
                cust_code = rs.getInt("customer_code");
            }
            rs.close();

            String sql1 = "DELETE FROM payment WHERE customer_code="+cust_code;
            stmt.executeUpdate(sql1);

            String sql2 = "DELETE FROM purchase WHERE card_number="+card_for_delete;
            stmt.executeUpdate(sql2);

            String sql3 = "DELETE FROM credit_card WHERE card_number="+card_for_delete;
            stmt.executeUpdate(sql3);

            stmt.close();
            dbcon.close();

            }
        catch(SQLException e)
        {
        System.out.print("SQLException: ");
        System.out.println(e.getMessage());}



    }