Database Error w/o error number in the DB_driver.php

[eluser]Unknown[/eluser]
I'm new to Oracle and I'm using Wamp.
I already have an existing connection between CI using Wamp and MySql, and now I'm required to connect it to Oracle.

I'm getting this error and I can't find any solutions yet (I've searched on some posts already).

A Database Error Occurred
Error Number:

SELECT * FROM "project_users" WHERE "userid" = 'user1' AND "password" = 'iamuser1'

Filename: C:\wamp\www\project\system\database\DB_driver.php

Line Number: 330

Can someone help me on this? BTW, I have Oracle 10g Express Edition and CodeIgniter Version 1.0. Thanks for any help.

This is the code in line 330:

Code:

if (FALSE === ($this->result_id = $this->simple_query($sql)))
  {
   if ($this->save_queries == TRUE)
   {
    $this->query_times[] = 0;
   }

   $this->_trans_status = FALSE;

   if ($this->db_debug)
   {
    $error_no = $this->_error_number();
    $error_msg = $this->_error_message();

    $this->trans_complete();

    log_message('error', 'Query error: '.$error_msg);

    return $this->display_error(

          array(
            'Error Number: '.$error_no,
            $error_msg,
            $sql
           )
          );  //   <------this line is 330
   }
   return FALSE;
  }