Stack Overflow Question: CakePHP Containable with HABTM

-- See http://stackoverflow.com/questions/13826474/cakephp-containable-with-habtm
--
-- phpMyAdmin SQL Dump
-- version 3.5.1
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Dec 11, 2012 at 11:37 AM
-- Server version: 5.5.25
-- PHP Version: 5.2.17

SET SQL_MODE="NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";

--
-- Database: `test_db`
--

-- --------------------------------------------------------

--
-- Table structure for table `courses`
--

CREATE TABLE `courses` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `teacher_id` int(10) unsigned NOT NULL,
  `title` varchar(100) NOT NULL,
  `start_date` date NOT NULL,
  `end_date` date NOT NULL,
  `created` datetime NOT NULL,
  `modified` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=3 ;

--
-- Dumping data for table `courses`
--

INSERT INTO `courses` (`id`, `teacher_id`, `title`, `start_date`, `end_date`, `created`, `modified`) VALUES
(1, 1, 'Introduction to Improvisation', '2012-12-17', '2012-12-21', '2012-12-11 00:00:00', '2012-12-11 00:00:00'),
(2, 2, 'Painting', '2012-12-17', '2012-12-21', '2012-12-11 00:00:00', '2012-12-11 00:00:00');

-- --------------------------------------------------------

--
-- Table structure for table `courses_students`
--

CREATE TABLE `courses_students` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `course_id` int(10) unsigned NOT NULL,
  `student_id` int(10) unsigned NOT NULL,
  `is_approved` tinyint(1) unsigned DEFAULT NULL,
  `created` datetime NOT NULL,
  `modified` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=5 ;

--
-- Dumping data for table `courses_students`
--

INSERT INTO `courses_students` (`id`, `course_id`, `student_id`, `is_approved`, `created`, `modified`) VALUES
(1, 1, 1, NULL, '2012-12-11 00:00:00', '2012-12-11 00:00:00'),
(2, 2, 1, 1, '2012-12-11 00:00:00', '2012-12-11 00:00:00'),
(3, 1, 2, 1, '2012-12-11 00:00:00', '2012-12-11 00:00:00'),
(4, 2, 2, NULL, '2012-12-11 00:00:00', '2012-12-11 00:00:00');

-- --------------------------------------------------------

--
-- Table structure for table `students`
--

CREATE TABLE `students` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `first_name` varchar(100) NOT NULL,
  `last_name` varchar(100) NOT NULL,
  `grade` tinyint(3) unsigned NOT NULL,
  `created` datetime NOT NULL,
  `modified` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=3 ;

--
-- Dumping data for table `students`
--

INSERT INTO `students` (`id`, `first_name`, `last_name`, `grade`, `created`, `modified`) VALUES
(1, 'Bill', 'Brown', 9, '2012-12-11 00:00:00', '2012-12-11 00:00:00'),
(2, 'Sally', 'Smith', 10, '2012-12-11 00:00:00', '2012-12-11 00:00:00');

-- --------------------------------------------------------

--
-- Table structure for table `teachers`
--

CREATE TABLE `teachers` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  `first_name` varchar(100) NOT NULL,
  `last_name` varchar(100) NOT NULL,
  `created` datetime NOT NULL,
  `modified` datetime NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB  DEFAULT CHARSET=latin1 AUTO_INCREMENT=3 ;

--
-- Dumping data for table `teachers`
--

INSERT INTO `teachers` (`id`, `first_name`, `last_name`, `created`, `modified`) VALUES
(1, 'John', 'Doe', '2012-12-11 00:00:00', '2012-12-11 00:00:00'),
(2, 'Jane', 'Doe', '2012-12-11 00:00:00', '2012-12-11 00:00:00');