Cannot detect error in the following jdbc code

replacing it with

package p1;



import java.sql.*;

public class jdbcDemo

{

    public static void main(String args[])
    { int id = 0;
    try
    { Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
       Connection con = DriverManager.getConnection("jdbc:odbc:loginDSN");
       Connection con1 = DriverManager.getConnection("jdbc:odbc:loginDSN");
      Statement stat = con.createStatement();
      System.out.println("got connection");
      ResultSet rs = stat.executeQuery("Select max(UID) from mytable");
      while(rs.next())
      { id=rs.getInt(1);
      }
      id++;
      System.out.println(id);
      PreparedStatement ps = con1.prepareStatement("Insert into mytable(UID,Username,Password) values(?,?,?)");
      ps.setInt(1,id);
      ps.setString(2,"abhi");
      ps.setString(3,"bindra");


     ps.executeUpdate();

        }
    catch(Exception e)
    {

       e.printStackTrace();
    }

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}
}

the output is

got connection 6

but the changes are no reflected :(

You are trying to INSERT a new UID with the current MAX(UID). I imagine UID is the Primary Key, thus requiring uniqueness. Either add one to id during the insert (also using WhiteFang34's suggestion), use a sequence, or some other mechanism for autoupdating the column (autonumber in MySQL for instance).

Since you're reading UID as an int, you might need to set it as one too. You also likely need to increase it by one since you're currently using the max(UID) that already exists.

ps.setInt(1, id + 1);

Or perhaps you don't need to specify it at all because it's an auto-incrementing column?