// Remove all data from availability and completion tables
    // associated with course-modules belonging to this course.
    // Note this is done even if the features are not enabled
    // now, in case they were enabled previously.
    $DB->delete_records_select(
        'course_modules_completion',
        'coursemoduleid IN (SELECT id from {course_modules} WHERE course = ?)',
        array($courseid));

    // Iterate over the list of course modules, and for
    // each, call the associated plugin's routine to
    // delete the instance, delete the course module
    // entry. After the last course module for a given
    // plugin is removed, call the plugin's broader
    // method to delete a course, if it exists.
    $system_modules      = core_component::get_plugin_list('mod');
    $module_name         =
    $module_dir          =
    $module_del_instance =
    $module_del_course   =  '';
    $module_installed    = false;

    // Get the course modules for this course, sorted
    // by module name
    $course_modules = $DB->get_records_sql(
        "SELECT cm.*, m.name
           FROM {course_modules} cm
           JOIN {modules} m ON cm.module = m.id
          WHERE cm.course = :courseid ORDER BY m.name",
        array('courseid' => $courseid));

    foreach ($course_modules as $cm) {

        // Looking at a different module since last loop iteration?
        if ($module_name != $cm->name) {

            // Before setting up for the next module, call current
            // module's course delete routine, if it exists.
            if ($module_installed && function_exists($module_del_course)) {
                $module_del_course($course, $showfeedback);
            }

            // Indicate finished with the current module
            if ($module_installed && $showfeedback) {
                echo $OUTPUT->notification($strdeleted . get_string('pluginname', $module_name), 'notifysuccess');
            }

            $module_name = $cm->name;

            // Set up for the next module if it is valid
            if (array_key_exists($module_name, $system_modules)) {
                $module_installed    = true;
                $module_dir          = $system_modules[$module_name];
                $module_del_instance = $module_name . '_delete_instance';
                $module_del_course   = $module_name . '_delete_course';
                include_once("$module_dir/lib.php");
            } else {
                // This mod doesn't appear in the list of installed
                // mods, so don't call any of its library functions
                // even though the code might still be on disk
                $module_installed    = false;
                $module_dir          =
                $module_del_instance =
                $module_del_course   = '';
            }

        } // if ($module_name != $cm->name)

        // Delete activity context questions and question categories.
        question_delete_activity($cm, $showfeedback);

        if ($module_installed) {
            // If module supplies method to delete instance, call it
            if (function_exists($module_del_instance)) {
                $module_del_instance($cm->instance);
            } else {
                // Otherwise, indicate module does not provide an
                // expected callback method, and attempt to directly
                // remove rows using expected names for table/column
                // squelching any resulting exceptions (e.g. table
                // not found).
                debugging("Defective module '{$module_name}' detected when deleting course contents: missing function {$module_del_instance}()!");
                try { $DB->delete_records($module_name, array('id' => $cm->instance)); }
                catch (Exception $e) {}
            }
        }

        // Remove the course module row and its context, regardless of
        // whether the module appears to be installed
        context_helper::delete_instance(CONTEXT_MODULE, $cm->id);
        $DB->delete_records('course_modules', array('id' => $cm->id));

    } // foreach $cm

    // Call last module's course delete routine
    if ($module_installed && function_exists($module_del_course)) {
        $module_del_course($course, $showfeedback);
    }

    // Indicate finished with the last module
    if ($module_installed && $showfeedback) {
        echo $OUTPUT->notification($strdeleted . get_string('pluginname', $module_name), 'notifysuccess');
    }