INSERT,DELETE AND COUNT THE RECORDS IN DBMS WITH JAVA

INSERT THE RECORD
import java.io.DataInputStream;
import java.sql.*;
public class NewClass
{
    public static void main(String args[])throws Exception
    {
  DataInputStream din=new DataInputStream(System.in);
 Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con=DriverManager.getConnection("jdbc:derby://localhost:1527/kbn","kbn","kbn");
       Statement st=con.createStatement();
System.out.println("enter student number");
         int no=Integer.parseInt(din.readLine());
          System.out.println("enter student name");
         String name=din.readLine();
         String qry="insert into student values("+no+",'"+name+"')";
         int res=st.executeUpdate(qry);
         if(res==0)
             System.out.println("record not inserted");
         else
             System.out.println("record  inserted");
         
        
     }
}

COUNT THE RECORDS
import java.io.DataInputStream;
import java.sql.*;
public class NewClass
{
    public static void main(String args[])throws Exception
    {
  DataInputStream din=new DataInputStream(System.in);
 Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con=DriverManager.getConnection("jdbc:derby://localhost:1527/kbn","kbn","kbn");
       Statement st=con.createStatement();
ResultSet rs=st.executeQuery("select count(*) from student");
      
       if(rs.next())
       {
           int count=rs.getInt(1);
           System.out.println("no of records in the table is :"+count);
       }
 }
}

DELETE THE RECORDS
import java.io.DataInputStream;
import java.sql.*;
public class NewClass
{
    public static void main(String args[])throws Exception
    {
  DataInputStream din=new DataInputStream(System.in);
System.out.println("enter row to delete");
    int no=Integer.parseInt(din.readLine());
 Class.forName("org.apache.derby.jdbc.ClientDriver");
        Connection con=DriverManager.getConnection("jdbc:derby://localhost:1527/kbn","kbn","kbn");
       Statement st=con.createStatement();
String qry="delete from student where sid="+no;
       System.out.println(qry);
          int res=st.executeUpdate(qry);
        if(res==0)
            System.out.println("record not found");
        else
            System.out.println("record deleted"+res);
}
}