function question_cwqpfs_to_update($categories = null)
{
    global $CFG;
    $tofix = array();
    $result = true;
    //any cats with questions picking from subcats?
    if (!($cwqpfs = get_records_sql_menu("SELECT DISTINCT qc.id, 1 " . "FROM {$CFG->prefix}question q, {$CFG->prefix}question_categories qc " . "WHERE q.qtype='random' AND qc.id = q.category AND " . sql_compare_text('q.questiontext') . " = '1'"))) {
        return array();
    } else {
        if ($categories === null) {
            $categories = get_records('question_categories');
        }
        $categorychildparents = array();
        foreach ($categories as $id => $category) {
            $categorychildparents[$category->course][$id] = $category->parent;
        }
        foreach ($categories as $id => $category) {
            if (FALSE !== array_key_exists($category->parent, $categorychildparents[$category->course])) {
                //this is not a top level cat
                continue;
                //go to next category
            } else {
                $tofix += question_cwqpfs_check_children($id, $categories, $categorychildparents[$category->course], $cwqpfs);
            }
        }
    }
    return $tofix;
}

 /**
  * This function sets up options of otag select element. This is called from definition and also
  * after adding new official tags with the add tag button.
  *
  */
 function otags_select_setup()
 {
     global $CFG;
     $mform =& $this->_form;
     $otagsselect =& $mform->getElement('otags');
     $otagsselect->removeOptions();
     if ($otags = get_records_sql_menu('SELECT id, text from ' . $CFG->prefix . 'tags WHERE type=\'official\' ORDER by text ASC')) {
         $otagsselect->loadArray($otags);
     }
 }

function handle_individual($usersid)
{
    global $CFG;
    $sql = "SELECT id, path FROM {$CFG->prefix}block_student_person\n                        WHERE (path != 'NA' OR path != 0)\n                          AND usersid = {$usersid}";
    $assignments = get_records_sql_menu($sql);
    if ($assignments) {
        return handle_person($assignments);
    }
    return '';
}

 /**
  * This function sets up options of otag select element. This is called from definition and also
  * after adding new official tags with the add tag button.
  *
  */
 function otags_select_setup()
 {
     global $CFG;
     $mform =& $this->_form;
     if ($otagsselect =& $mform->getElement('otags')) {
         $otagsselect->removeOptions();
     }
     $namefield = empty($CFG->keeptagnamecase) ? 'name' : 'rawname';
     if ($otags = get_records_sql_menu('SELECT id, ' . $namefield . ' from ' . $CFG->prefix . 'tag WHERE tagtype=\'official\' ORDER by name ASC')) {
         $otagsselect->loadArray($otags);
     }
 }

 function display_search_field($value = '')
 {
     global $CFG;
     $temp = get_records_sql_menu('SELECT id, content from ' . $CFG->prefix . 'data_content WHERE fieldid=' . $this->field->id . ' GROUP BY content ORDER BY content');
     $options = array();
     if (!empty($temp)) {
         $options[''] = '';
         //Make first index blank.
         foreach ($temp as $key) {
             $options[$key] = $key;
             //Build following indicies from the sql.
         }
     }
     return choose_from_menu($options, 'f_' . $this->field->id, $value, 'choose', '', 0, true);
 }

 function display_search_field($value = '')
 {
     global $CFG;
     $lats = get_records_sql_menu('SELECT id, content from ' . $CFG->prefix . 'data_content WHERE fieldid=' . $this->field->id . ' GROUP BY content ORDER BY content');
     $longs = get_records_sql_menu('SELECT id, content1 from ' . $CFG->prefix . 'data_content WHERE fieldid=' . $this->field->id . ' GROUP BY content ORDER BY content');
     $options = array();
     if (!empty($lats) && !empty($longs)) {
         $options[''] = '';
         // Make first index blank.
         foreach ($lats as $key => $temp) {
             $options[$temp . ',' . $longs[$key]] = $temp . ',' . $longs[$key];
         }
     }
     return choose_from_menu($options, 'f_' . $this->field->id, $value, 'choose', '', 0, true);
 }

 function init()
 {
     global $CFG;
     // All the years to choose from
     // All the colleges to choose from
     // All the majors to choose from
     $fields = array('years' => 'year', 'colleges' => 'college', 'majors' => 'classification');
     $fields = array_map('special_sql', $fields);
     $this->fields = $fields;
     // All the current assignments in this category
     $sql = "SELECT id, path\n                FROM {$CFG->prefix}block_student_academics\n                WHERE path != 'NA'\n                Group By path";
     $inter = get_records_sql_menu($sql);
     $assignments = array_values(array(0 => 'NA') + (!$inter ? array() : $inter));
     $assignments = array_combine($assignments, $assignments);
     $assignments['NA'] = 'NA/NA/NA';
     $this->current_assignments = $assignments;
 }

 function init()
 {
     global $CFG;
     // Get user capabilities
     $cap_sql = "SELECT rc.id, rc.capability\n                        FROM {$CFG->prefix}role_assignments ra,\n                             {$CFG->prefix}role_capabilities rc\n                        WHERE ra.userid = {$this->userid}\n                          AND ra.roleid = rc.roleid\n                          AND rc.capability IN ('" . implode("','", $this->user_caps) . "')";
     $capabilities = get_records_sql_menu($cap_sql);
     // Get all the internal assignments
     $map = create_function('$field', '
             return "SELECT DISTINCT(u.id), u.firstname, u.lastname
                 FROM ' . $CFG->prefix . 'user u,
                      ' . $CFG->prefix . 'block_student_{$field} a,
                      ' . $CFG->prefix . 'role_assignments ra,
                      ' . $CFG->prefix . 'role_capabilities rc
                 WHERE u.id = a.usersid
                   AND ra.userid = u.id
                   AND ra.roleid = rc.roleid
                   AND rc.capability IN (\'' . implode("','", array_values($capabilities)) . '\')
                 GROUP BY u.id";');
     $sql = implode(') UNION (', array_map($map, array('sports', 'academics', 'person')));
     $this->mentors = array_map('flatten_mentors', get_records_sql('(' . $sql . ') ORDER BY lastname'));
 }

function question_insert_c_and_q_ids_for_module($backup_unique_code, $course, $modulename, $instances)
{
    global $CFG;
    $status = true;
    // using 'dummykeyname' in sql because otherwise get_records_sql_menu returns an error
    // if two key names are the same.
    $cmcontexts = array();
    if (!empty($instances)) {
        $cmcontexts = get_records_sql_menu("SELECT c.id, c.id AS dummykeyname FROM {$CFG->prefix}modules m,\n                                                        {$CFG->prefix}course_modules cm,\n                                                        {$CFG->prefix}context c\n                               WHERE m.name = '{$modulename}' AND m.id = cm.module AND cm.id = c.instanceid\n                                    AND c.contextlevel = " . CONTEXT_MODULE . " AND cm.course = {$course}\n                                    AND cm.instance IN (" . implode(',', array_keys($instances)) . ")");
    }
    if ($cmcontexts) {
        $status = $status && execute_sql("INSERT INTO {$CFG->prefix}backup_ids\n                                       (backup_code, table_name, old_id, info)\n                                   SELECT '{$backup_unique_code}', 'question_categories', qc.id, '{$modulename}'\n                                   FROM {$CFG->prefix}question_categories qc\n                                   WHERE qc.contextid IN (" . join(array_keys($cmcontexts), ', ') . ")", false);
    }
    $status = $status && question_insert_q_ids($backup_unique_code, $modulename);
    return $status;
}

 function set_data_attempt(&$attempt, &$strftimedate, &$strftimetime, &$blank)
 {
     global $CFG;
     $records = get_records_sql_menu("\n\t\t\tSELECT userid, MAX(time) AS logintime\n\t\t\tFROM {$CFG->prefix}log\n\t\t\tWHERE userid={$attempt->userid} AND action='login' AND time<{$attempt->timestart}\n\t\t\tGROUP BY userid\n\t\t");
     if (empty($records)) {
         $logindate = $blank;
         $logintime = $blank;
     } else {
         $logintime = $records[$attempt->userid];
         $logindate = trim(userdate($logintime, $strftimedate));
         $logintime = trim(userdate($logintime, $strftimetime));
     }
     $records = get_records_sql_menu("\n\t\t\tSELECT userid, MIN(time) AS logouttime\n\t\t\tFROM {$CFG->prefix}log\n\t\t\tWHERE userid={$attempt->userid} AND action='logout' AND time>{$attempt->cr_timefinish}\n\t\t\tGROUP BY userid\n\t\t");
     if (empty($records)) {
         $logouttime = $blank;
     } else {
         $logouttime = $records[$attempt->userid];
         $logouttime = trim(userdate($logouttime, $strftimetime));
     }
     $this->data['attempt'] = array('logindate' => $logindate, 'logintime' => $logintime, 'logouttime' => $logouttime, 'number' => $attempt->attempt, 'start' => trim(userdate($attempt->timestart, $strftimetime)), 'finish' => trim(userdate($attempt->cr_timefinish, $strftimetime)));
 }

 function display($quiz, $cm, $course)
 {
     /// This function just displays the report
     global $CFG, $SESSION, $db, $QTYPES;
     $strnoquiz = get_string('noquiz', 'quiz');
     $strnoattempts = get_string('noattempts', 'quiz');
     /// Only print headers if not asked to download data
     $download = optional_param('download', NULL);
     if (!$download) {
         $this->print_header_and_tabs($cm, $course, $quiz, $reportmode = "analysis");
     }
     /// Construct the table for this particular report
     if (!$quiz->questions) {
         print_heading($strnoattempts);
         return true;
     }
     /// Check to see if groups are being used in this quiz
     if ($groupmode = groupmode($course, $cm)) {
         // Groups are being used
         if (!$download) {
             $currentgroup = setup_and_print_groups($course, $groupmode, "report.php?id={$cm->id}&mode=analysis");
         } else {
             $currentgroup = get_and_set_current_group($course, $groupmode);
         }
     } else {
         $currentgroup = get_and_set_current_group($course, $groupmode);
     }
     // set Table and Analysis stats options
     if (!isset($SESSION->quiz_analysis_table)) {
         $SESSION->quiz_analysis_table = array('attemptselection' => 0, 'lowmarklimit' => 0, 'pagesize' => 10);
     }
     foreach ($SESSION->quiz_analysis_table as $option => $value) {
         $urlparam = optional_param($option, NULL);
         if ($urlparam === NULL) {
             ${$option} = $value;
         } else {
             ${$option} = $SESSION->quiz_analysis_table[$option] = $urlparam;
         }
     }
     $scorelimit = $quiz->sumgrades * $lowmarklimit / 100;
     // ULPGC ecastro DEBUG this is here to allow for different SQL to select attempts
     switch ($attemptselection) {
         case QUIZ_ALLATTEMPTS:
             $limit = '';
             $group = '';
             break;
         case QUIZ_HIGHESTATTEMPT:
             $limit = ', max(qa.sumgrades) ';
             $group = ' GROUP BY qa.userid ';
             break;
         case QUIZ_FIRSTATTEMPT:
             $limit = ', min(qa.timemodified) ';
             $group = ' GROUP BY qa.userid ';
             break;
         case QUIZ_LASTATTEMPT:
             $limit = ', max(qa.timemodified) ';
             $group = ' GROUP BY qa.userid ';
             break;
     }
     if ($attemptselection != QUIZ_ALLATTEMPTS) {
         $sql = 'SELECT qa.userid ' . $limit . 'FROM ' . $CFG->prefix . 'user u LEFT JOIN ' . $CFG->prefix . 'quiz_attempts qa ON u.id = qa.userid ' . 'WHERE qa.quiz = ' . $quiz->id . ' AND qa.preview = 0 ' . $group;
         $usermax = get_records_sql_menu($sql);
     }
     $groupmembers = '';
     $groupwhere = '';
     //Add this to the SQL to show only group users
     if ($currentgroup) {
         $groupmembers = ', ' . groups_members_from_sql();
         $groupwhere = ' AND ' . groups_members_where_sql($currentgroup, 'u.id');
     }
     $sql = 'SELECT  qa.* FROM ' . $CFG->prefix . 'quiz_attempts qa, ' . $CFG->prefix . 'user u ' . $groupmembers . 'WHERE u.id = qa.userid AND qa.quiz = ' . $quiz->id . ' AND qa.preview = 0 AND ( qa.sumgrades >= ' . $scorelimit . ' ) ' . $groupwhere;
     // ^^^^^^ es posible seleccionar aqu TODOS los quizzes, como quiere Jussi,
     // pero habra que llevar la cuenta ed cada quiz para restaura las preguntas (quizquestions, states)
     /// Fetch the attempts
     $attempts = get_records_sql($sql);
     if (empty($attempts)) {
         print_heading(get_string('nothingtodisplay'));
         $this->print_options_form($quiz, $cm, $attemptselection, $lowmarklimit, $pagesize);
         return true;
     }
     /// Here we rewiew all attempts and record data to construct the table
     $questions = array();
     $statstable = array();
     $questionarray = array();
     foreach ($attempts as $attempt) {
         $questionarray[] = quiz_questions_in_quiz($attempt->layout);
     }
     $questionlist = quiz_questions_in_quiz(implode(",", $questionarray));
     $questionarray = array_unique(explode(",", $questionlist));
     $questionlist = implode(",", $questionarray);
     unset($questionarray);
     foreach ($attempts as $attempt) {
         switch ($attemptselection) {
             case QUIZ_ALLATTEMPTS:
                 $userscore = 0;
                 // can be anything, not used
                 break;
             case QUIZ_HIGHESTATTEMPT:
                 $userscore = $attempt->sumgrades;
                 break;
//.........这里部分代码省略.........

/** 
 *  sends an email to the teachers of the course where the given feedback is placed.
 *  @param object $cm the coursemodule-record
 *  @param $feedback
 *  @param $course
 *  @param $userid
 *  @return void
 */
function feedback_send_email($cm, $feedback, $course, $userid)
{
    global $CFG;
    if ($feedback->email_notification == 0) {
        // No need to do anything
        return;
    }
    $user = get_record('user', 'id', $userid);
    if (groupmode($course, $cm) == SEPARATEGROUPS) {
        // Separate groups are being used
        $groups = get_records_sql_menu("SELECT g.name, g.id\n                                          FROM {$CFG->prefix}groups g,\n                                                 {$CFG->prefix}groups_members m\n                                          WHERE g.courseid = '{$course->id}'\n                                             AND g.id = m.groupid\n                                             AND m.userid = '{$userid}'\n                                             ORDER BY name ASC");
        $groups = array_values($groups);
        $teachers = feedback_get_receivemail_users($cm->id, $groups);
    } else {
        $teachers = feedback_get_receivemail_users($cm->id);
    }
    if ($teachers) {
        $strfeedbacks = get_string('modulenameplural', 'feedback');
        $strfeedback = get_string('modulename', 'feedback');
        $strcompleted = get_string('completed', 'feedback');
        $printusername = $feedback->anonymous == FEEDBACK_ANONYMOUS_NO ? fullname($user) : get_string('anonymous_user', 'feedback');
        foreach ($teachers as $teacher) {
            unset($info);
            $info->username = $printusername;
            $info->feedback = format_string($feedback->name, true);
            $info->url = $CFG->wwwroot . '/mod/feedback/show_entries.php?id=' . $cm->id . '&userid=' . $userid . '&do_show=showentries';
            $postsubject = $strcompleted . ': ' . $info->username . ' -> ' . $feedback->name;
            $posttext = feedback_send_email_text($info, $course);
            $posthtml = $teacher->mailformat == 1 ? feedback_send_email_html($info, $course, $cm) : '';
            if ($feedback->anonymous == FEEDBACK_ANONYMOUS_NO) {
                @email_to_user($teacher, $user, $postsubject, $posttext, $posthtml);
            } else {
                @email_to_user($teacher, $teacher, $postsubject, $posttext, $posthtml);
            }
        }
    }
}

function quiz_report_grade_bands($bandwidth, $bands, $quizid, $useridlist = '')
{
    global $CFG;
    $sql = "SELECT\n        FLOOR(qg.grade/{$bandwidth}) AS band,\n        COUNT(1) AS num\n    FROM\n        {$CFG->prefix}quiz_grades qg, \n        {$CFG->prefix}quiz q\n    WHERE qg.quiz = q.id AND qg.quiz = {$quizid} \n            " . ($useridlist ? "AND qg.userid IN ({$useridlist}) " : '') . "\n    GROUP BY FLOOR(qg.grade/{$bandwidth})\n    ORDER BY band";
    if (!($data = get_records_sql_menu($sql))) {
        $data = array();
    }
    //need to create array elements with values 0 at indexes where there is no element
    $data = $data + array_fill(0, $bands + 1, 0);
    ksort($data);
    //place the maximum (prefect grade) into the last band i.e. make last
    //band for example 9 <= g <=10 (where 10 is the perfect grade) rather than
    //just 9 <= g <10.
    $data[$bands - 1] += $data[$bands];
    unset($data[$bands]);
    return $data;
}

        }
        $post->id = $existing->id;
        $post->subject = $existing->subject;
        $post->summary = $existing->summary;
        $post->publishstate = $existing->publishstate;
        $post->format = $existing->format;
        $post->action = $action;
        $strformheading = get_string('updateentrywithid', 'blog');
        if ($ptags = get_records_sql_menu("SELECT t.id, t.text FROM\n                                     {$CFG->prefix}tags t,\n                                     {$CFG->prefix}blog_tag_instance bti\n                                     WHERE t.id = bti.tagid\n                                     AND t.type = 'personal'\n                                     AND bti.entryid = {$post->id}")) {
            $post->ptags = implode(', ', $ptags);
        } else {
            //$idsql = " AND bti.entryid = 0";
            //was used but seems redundant.
            $post->ptags = '';
        }
        if ($otags = get_records_sql_menu("SELECT t.id, t.text FROM\n                                     {$CFG->prefix}tags t,\n                                     {$CFG->prefix}blog_tag_instance bti\n                                     WHERE t.id = bti.tagid\n                                     AND t.type = 'official'\n                                     AND bti.entryid = {$post->id}")) {
            $post->otags = array_keys($otags);
        }
        break;
    default:
        error('Unknown action!');
}
// done here in order to allow deleting of posts with wrong user id above
if (!($user = get_record('user', 'id', $userid))) {
    error('Incorrect user id');
}
print_header("{$SITE->shortname}: {$strblogs}", $SITE->fullname, '<a href="' . $CFG->wwwroot . '/user/view.php?id=' . $userid . '">' . fullname($user) . '</a> ->
                <a href="' . $CFG->wwwroot . '/blog/index.php?userid=' . $userid . '">' . $strblogs . '</a> -> ' . $strformheading, '', '', true);
$blogeditform->set_data($post);
$blogeditform->display();
print_footer();

function lesson_grades($lessonid)
{
    /// Must return an array of grades for a given instance of this module,
    /// indexed by user.  It also returns a maximum allowed grade.
    global $CFG;
    if (!($lesson = get_record("lesson", "id", $lessonid))) {
        return NULL;
    }
    if ($lesson->retake) {
        if ($lesson->usemaxgrade) {
            $grades = get_records_sql_menu("SELECT userid,MAX(grade) FROM {$CFG->prefix}lesson_grades WHERE\n            lessonid = {$lessonid} GROUP BY userid");
        } else {
            $grades = get_records_sql_menu("SELECT userid,AVG(grade) FROM {$CFG->prefix}lesson_grades WHERE\n            lessonid = {$lessonid} GROUP BY userid");
        }
    } else {
        // Retakes is turned Off; only count first attempt
        $firstgrades = get_records_sql("SELECT userid, MIN(completed), grade FROM {$CFG->prefix}lesson_grades WHERE lessonid = {$lessonid} GROUP BY userid");
        $grades = array();
        if (!empty($firstgrades)) {
            foreach ($firstgrades as $userid => $info) {
                $grades[$userid] = $info->grade;
            }
        }
    }
    // convert grades from percentages and tidy the numbers
    if (!$lesson->practice) {
        // dont display practice lessons
        if ($grades) {
            foreach ($grades as $userid => $grade) {
                $return->grades[$userid] = number_format($grade * $lesson->grade / 100.0, 1);
            }
        }
        $return->maxgrade = $lesson->grade;
        return $return;
    } else {
        return NULL;
    }
}

$buttontext = update_module_button($cm->id, $course->id, $strfeedback);
$navlinks = array();
$navlinks[] = array('name' => $strfeedbacks, 'link' => "index.php?id={$course->id}", 'type' => 'activity');
$navlinks[] = array('name' => format_string($feedback->name), 'link' => "", 'type' => 'activityinstance');
$navigation = build_navigation($navlinks);
print_header_simple(format_string($feedback->name), "", $navigation, "", "", true, $buttontext, navmenu($course, $cm));
include 'tabs.php';
// print_simple_box(get_string('mapcourseinfo', 'feedback'), 'center', '80%');
print_box(get_string('mapcourseinfo', 'feedback'), 'generalbox boxaligncenter boxwidthwide');
// print_simple_box_start('center', '70%');
print_box_start('generalbox boxaligncenter boxwidthwide');
echo '<form method="post">';
echo '<input type="hidden" name="id" value="' . $id . '" />';
echo '<input type="hidden" name="sesskey" value="' . $USER->sesskey . '" />';
$sql = "select c.id, c.shortname from {$CFG->prefix}course c\n            where\n                c.shortname " . sql_ilike() . " '%{$searchcourse}%'\n            OR c.fullname " . sql_ilike() . " '%{$searchcourse}%'";
if (($courses = get_records_sql_menu($sql)) && !empty($searchcourse)) {
    echo ' ' . get_string('courses') . ': ';
    choose_from_menu($courses, 'coursefilter', $coursefilter, 'choose');
    echo '<input type="submit" value="' . get_string('mapcourse', 'feedback') . '"/>';
    helpbutton('mapcourses', '', 'feedback', true, true);
    echo '<input type="button" value="' . get_string('searchagain') . '" onclick="document.location=\'mapcourse.php?id=' . $id . '\'"/>';
    echo '<input type="hidden" name="searchcourse" value="' . $searchcourse . '"/>';
    echo '<input type="hidden" name="feedbackid" value="' . $feedback->id . '"/>';
    helpbutton('searchcourses', '', 'feedback', true, true);
} else {
    echo '<input type="text" name="searchcourse" value="' . $searchcourse . '"/> <input type="submit" value="' . get_string('searchcourses') . '"/>';
    helpbutton('searchcourses', '', 'feedback', true, true);
}
echo '</form>';
if ($coursemap = feedback_get_courses_from_sitecourse_map($feedback->id)) {
    $table = new flexible_table('coursemaps');

 function getCoursesPerSemester($semester = null)
 {
     global $CFG;
     $sem = "";
     if (is_array($semester)) {
         $sem = "AND sec.semestersid IN (" . implode(',', $semester) . ")";
     } else {
         if (is_numeric($semester)) {
             $sem = "AND sec.semestersid = {$semester}";
         }
     }
     $sql = "SELECT sec.semestersid, COUNT(cou.id) as count\n                    FROM {$CFG->prefix}block_courseprefs_sections sec,\n                         {$CFG->prefix}block_courseprefs_courses cou,\n                         {$CFG->prefix}block_courseprefs_teachers t\n                    WHERE sec.coursesid = cou.id\n                      AND t.sectionsid = sec.id\n                      AND t.usersid = {$this->id}\n                      AND t.primary_flag = 1\n                      AND (t.status = 'enroll' OR t.status = 'enrolled')\n                      AND sec.status != 'unwanted'\n                      {$sem}\n                 GROUP BY sec.semestersid";
     $results = get_records_sql_menu($sql);
     return $results;
 }

print_js_call('capability_report.cap_filter_init', array(get_string('search')));
echo '</form>';
print_box_end();
// If we have a capability, generate the report.
if ($capability) {
    // Work out the bits needed for the SQL WHERE clauses.
    $sqlroletest = '';
    if (count($cleanedroleids) != count($allroles)) {
        $sqlroletest = 'AND roleid IN (' . implode(',', $cleanedroleids) . ')';
    }
    // Get all the role_capabilities rows for this capability - that is, all
    // role definitions, and all role overrides.
    $rolecaps = get_records_sql("\n            SELECT id, roleid, contextid, permission\n            FROM {role_capabilities}\n            WHERE capability = '{$capability}' {$sqlroletest}");
    // In order to display a nice tree of contexts, we need to get all the
    // ancestors of all the contexts in the query we just did.
    $relevantpaths = get_records_sql_menu("\n            SELECT DISTINCT con.path, 1\n            FROM {context} con JOIN {role_capabilities} rc ON rc.contextid = con.id\n            WHERE capability = '{$capability}' {$sqlroletest}");
    $requiredcontexts = array($systemcontext->id);
    if (!empty($relevantpaths)) {
        foreach ($relevantpaths as $path => $notused) {
            $requiredcontexts = array_merge($requiredcontexts, explode('/', trim($path, '/')));
        }
    }
    $requiredcontexts = array_unique($requiredcontexts);
    // Now load those contexts.
    if (count($requiredcontexts) > 0) {
        $contexts = get_sorted_contexts('ctx.id IN (' . implode(',', $requiredcontexts) . ')');
    }
    if (empty($contexts)) {
        $contexts = array();
    }
    // Prepare some empty arrays to hold the data we are about to compute.

 $db_names_function = $mod->name . '_db_names';
 $updates = array();
 if (file_exists($class_file)) {
     require_once $class_file;
     //if both required functions exist
     if (function_exists($delete_function) and function_exists($db_names_function) and function_exists($get_document_function)) {
         mtrace("Checking {$mod->name} module for updates.");
         $valuesArray = $db_names_function();
         if ($valuesArray) {
             foreach ($valuesArray as $values) {
                 $where = isset($values[5]) ? 'AND (' . $values[5] . ')' : '';
                 $itemtypes = $values[4] != '*' && $values[4] != 'any' ? " AND itemtype = '{$values[4]}' " : '';
                 //TODO: check 'in' syntax with other RDBMS' (add and update.php as well)
                 $table = SEARCH_DATABASE_TABLE;
                 $query = "\n                                SELECT \n                                    docid,\n                                    itemtype\n                                FROM \n                                    {$CFG->prefix}{$table}\n                                WHERE\n                                    doctype = '{$mod->name}'\n                                    {$itemtypes}\n                            ";
                 $docIds = get_records_sql_menu($query);
                 $docIdList = $docIds ? implode("','", array_keys($docIds)) : '';
                 $query = "\n                                SELECT \n                                    id, \n                                    {$values[0]} as docid\n                                FROM \n                                    {$CFG->prefix}{$values[1]} \n                                WHERE \n                                    {$values[3]} > {$indexdate} AND \n                                    id IN ('{$docIdList}')\n                                    {$where}\n                            ";
                 $records = get_records_sql($query);
                 if (is_array($records)) {
                     foreach ($records as $record) {
                         $updates[] = $delete_function($record->docid, $docIds[$record->docid]);
                     }
                 }
             }
             foreach ($updates as $update) {
                 ++$update_count;
                 //delete old document
                 $doc = $index->find("+docid:{$update->id} +doctype:{$mod->name} +itemtype:{$update->itemtype}");
                 //get the record, should only be one
                 foreach ($doc as $thisdoc) {

/**
 * Returns an array of names of quizzes that use this question
 *
 * @param object $questionid
 * @return array of strings
 */
function quiz_question_list_instances($questionid)
{
    global $CFG;
    // TODO: we should also consider other questions that are used by
    // random questions in this quiz, but that is very hard.
    $sql = "SELECT q.id, q.name\n            FROM {$CFG->prefix}quiz q\n            INNER JOIN\n                 {$CFG->prefix}quiz_question_instances qqi\n            ON q.id = qqi.quiz\n            WHERE qqi.question = '{$questionid}'";
    if ($instances = get_records_sql_menu($sql)) {
        return $instances;
    }
    return array();
}