function xmldb_assignment_upgrade($oldversion) {
    global $CFG, $DB, $OUTPUT;

    $dbman = $DB->get_manager();


    // Moodle v2.2.0 release upgrade line
    // Put any upgrade step following this

    // Moodle v2.3.0 release upgrade line
    // Put any upgrade step following this


    if ($oldversion < 2012061701) {
        // Fixed/updated numfiles field in assignment_submissions table to count the actual
        // number of files has been uploaded when sendformarking is disabled
        upgrade_set_timeout(600);  // increase excution time for in large sites
        $fs = get_file_storage();

        // Fetch the moduleid for use in the course_modules table
        $moduleid = $DB->get_field('modules', 'id', array('name' => 'assignment'), MUST_EXIST);

        $selectcount = 'SELECT COUNT(s.id) ';
        $select      = 'SELECT s.id, cm.id AS cmid ';
        $query       = 'FROM {assignment_submissions} s
                        JOIN {assignment} a ON a.id = s.assignment
                        JOIN {course_modules} cm ON a.id = cm.instance AND cm.module = :moduleid
                        WHERE assignmenttype = :assignmenttype';

        $params = array('moduleid' => $moduleid, 'assignmenttype' => 'upload');

        $countsubmissions = $DB->count_records_sql($selectcount.$query, $params);
        $submissions = $DB->get_recordset_sql($select.$query, $params);

        $pbar = new progress_bar('assignmentupgradenumfiles', 500, true);
        $i = 0;
        foreach ($submissions as $sub) {
            $i++;
            if ($context = context_module::instance($sub->cmid)) {
                $sub->numfiles = count($fs->get_area_files($context->id, 'mod_assignment', 'submission', $sub->id, 'sortorder', false));
                $DB->update_record('assignment_submissions', $sub);
            }
            $pbar->update($i, $countsubmissions, "Counting files of submissions ($i/$countsubmissions)");
        }
        $submissions->close();

        // assignment savepoint reached
        upgrade_mod_savepoint(true, 2012061701, 'assignment');
    }

    // Moodle v2.4.0 release upgrade line
    // Put any upgrade step following this


    // Moodle v2.5.0 release upgrade line.
    // Put any upgrade step following this.


    return true;
}

/**
 * xmldb_pcast_upgrade
 *
 * @param int $oldversion
 * @return bool
 */
function xmldb_pcast_upgrade($oldversion = 0)
{
    global $CFG, $THEME, $db;
    $result = true;
    /// And upgrade begins here. For each one, you'll need one
    /// block of code similar to the next one. Please, delete
    /// this comment lines once this file start handling proper
    /// upgrade code.
    /// if ($result && $oldversion < YYYYMMDD00) { //New version in version.php
    ///     $result = result of "/lib/ddllib.php" function calls
    /// }
    /// RatingArea Upgrade
    if ($oldversion < 2011080700) {
        // rating.component and rating.ratingarea have now been added as mandatory fields.
        // Presently you can only rate data entries so component = 'mod_pcast' and ratingarea = 'episode'
        // for all ratings with a pcast context.
        // We want to update all ratings that belong to a glossary context and don't already have a
        // component set.
        // This could take a while reset upgrade timeout to 5 min
        upgrade_set_timeout(60 * 20);
        $sql = "UPDATE {rating}\n                SET component = 'mod_pcast', ratingarea = 'episode'\n                WHERE contextid IN (\n                    SELECT ctx.id\n                      FROM {context} ctx\n                      JOIN {course_modules} cm ON cm.id = ctx.instanceid\n                      JOIN {modules} m ON m.id = cm.module\n                     WHERE ctx.contextlevel = 70 AND\n                           m.name = 'pcast'\n                ) AND component = 'unknown'";
        $DB->execute($sql);
        upgrade_mod_savepoint(true, 2011080700, 'pcast');
    }
    /// Final return of upgrade result (true/false) to Moodle. Must be
    /// always the last line in the script
    return true;
}

function xmldb_survey_upgrade($oldversion)
{
    global $CFG, $DB;
    $dbman = $DB->get_manager();
    //===== 1.9.0 upgrade line ======//
    if ($oldversion < 2009042002) {
        /// Define field introformat to be added to survey
        $table = new xmldb_table('survey');
        $field = new xmldb_field('introformat', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0', 'intro');
        /// Conditionally launch add field introformat
        if (!$dbman->field_exists($table, $field)) {
            $dbman->add_field($table, $field);
        }
        // conditionally migrate to html format in intro
        if ($CFG->texteditors !== 'textarea') {
            $rs = $DB->get_recordset('survey', array('introformat' => FORMAT_MOODLE), '', 'id,intro,introformat');
            foreach ($rs as $s) {
                $s->intro = text_to_html($s->intro, false, false, true);
                $s->introformat = FORMAT_HTML;
                $DB->update_record('survey', $s);
                upgrade_set_timeout();
            }
            $rs->close();
        }
        /// survey savepoint reached
        upgrade_mod_savepoint(true, 2009042002, 'survey');
    }
    return true;
}

function page_20_migrate_candidate($candidate, $fs, $format)
{
    global $CFG, $DB;
    upgrade_set_timeout();
    $page = new object();
    $page->course = $candidate->course;
    $page->name = $candidate->name;
    $page->intro = $candidate->intro;
    $page->introformat = $candidate->introformat;
    $page->content = $candidate->alltext;
    $page->contentformat = $format;
    $page->revision = 1;
    $page->timemodified = time();
    // convert links to old course files - let the automigration do the actual job
    $usedfiles = array("{$CFG->wwwroot}/file.php/{$page->course}/", "{$CFG->wwwroot}/file.php?file=/{$page->course}/");
    $page->content = str_ireplace($usedfiles, '@@PLUGINFILE@@/', $page->content);
    if (strpos($page->content, '@@PLUGINFILE@@/') === false) {
        $page->legacyfiles = RESOURCELIB_LEGACYFILES_NO;
    } else {
        $page->legacyfiles = RESOURCELIB_LEGACYFILES_ACTIVE;
    }
    $options = array('printheading' => 0, 'printintro' => 0);
    if ($candidate->popup) {
        $page->display = RESOURCELIB_DISPLAY_POPUP;
        if ($candidate->popup) {
            $rawoptions = explode(',', $candidate->popup);
            foreach ($rawoptions as $rawoption) {
                list($name, $value) = explode('=', trim($rawoption), 2);
                if ($value > 0 and ($name == 'width' or $name == 'height')) {
                    $options['popup' . $name] = $value;
                    continue;
                }
            }
        }
    } else {
        $page->display = RESOURCELIB_DISPLAY_OPEN;
    }
    $page->displayoptions = serialize($options);
    $page = resource_migrate_to_module('page', $candidate, $page);
    // now try to migrate files from site files
    // noite: this can not work for html pages or files with other relatively linked files :-(
    $siteid = get_site()->id;
    if (preg_match_all("|{$CFG->wwwroot}/file.php(\\?file=)?/{$siteid}(/[^\\s'\"&\\?#]+)|", $page->content, $matches)) {
        $context = get_context_instance(CONTEXT_MODULE, $candidate->cmid);
        $sitecontext = get_context_instance(CONTEXT_COURSE, $siteid);
        $file_record = array('contextid' => $context->id, 'filearea' => 'page_content', 'itemid' => 0);
        $fs = get_file_storage();
        foreach ($matches[2] as $i => $sitefile) {
            if (!($file = $fs->get_file_by_hash(sha1($sitecontext->id . 'course_content0' . $sitefile)))) {
                continue;
            }
            try {
                $fs->create_file_from_storedfile($file_record, $file);
                $page->content = str_replace($matches[0][$i], '@@PLUGINFILE@@' . $sitefile, $page->content);
            } catch (Exception $x) {
            }
        }
        $DB->update_record('page', $page);
    }
}

function xmldb_logstore_standard_upgrade($oldversion)
{
    global $CFG, $DB;
    $dbman = $DB->get_manager();
    // Moodle v2.8.0 release upgrade line.
    // Put any upgrade step following this.
    // Moodle v2.9.0 release upgrade line.
    // Put any upgrade step following this.
    // Moodle v3.0.0 release upgrade line.
    // Put any upgrade step following this.
    if ($oldversion < 2016041200) {
        // This could take a long time. Unfortunately, no way to know how long, and no way to do progress, so setting for 1 hour.
        upgrade_set_timeout(3600);
        // Define key contextid (foreign) to be added to logstore_standard_log.
        $table = new xmldb_table('logstore_standard_log');
        $key = new xmldb_key('contextid', XMLDB_KEY_FOREIGN, array('contextid'), 'context', array('id'));
        // Launch add key contextid.
        $dbman->add_key($table, $key);
        // Standard savepoint reached.
        upgrade_plugin_savepoint(true, 2016041200, 'logstore', 'standard');
    }
    // Moodle v3.1.0 release upgrade line.
    // Put any upgrade step following this.
    // Automatically generated Moodle v3.2.0 release upgrade line.
    // Put any upgrade step following this.
    return true;
}

/**
 * Migrate folder module data from 1.9 resource_old table to new older table
 * @return void
 */
function folder_20_migrate()
{
    global $CFG, $DB;
    require_once "{$CFG->libdir}/filelib.php";
    require_once "{$CFG->dirroot}/course/lib.php";
    if (!file_exists("{$CFG->dirroot}/mod/resource/db/upgradelib.php")) {
        // bad luck, somebody deleted resource module
        return;
    }
    require_once "{$CFG->dirroot}/mod/resource/db/upgradelib.php";
    // create resource_old table and copy resource table there if needed
    if (!resource_20_prepare_migration()) {
        // no modules or fresh install
        return;
    }
    if (!($candidates = $DB->get_recordset('resource_old', array('type' => 'directory', 'migrated' => 0)))) {
        return;
    }
    $fs = get_file_storage();
    foreach ($candidates as $candidate) {
        upgrade_set_timeout();
        $directory = '/' . trim($candidate->reference, '/') . '/';
        $directory = str_replace('//', '/', $directory);
        $folder = new object();
        $folder->course = $candidate->course;
        $folder->name = $candidate->name;
        $folder->intro = $candidate->intro;
        $folder->introformat = $candidate->introformat;
        $folder->revision = 1;
        $folder->timemodified = time();
        if (!($folder = resource_migrate_to_module('folder', $candidate, $folder))) {
            continue;
        }
        // copy files in given directory, skip moddata and backups!
        $context = get_context_instance(CONTEXT_MODULE, $candidate->cmid);
        $coursecontext = get_context_instance(CONTEXT_COURSE, $candidate->course);
        $files = $fs->get_directory_files($coursecontext->id, 'course_content', 0, $directory, true, true);
        $file_record = array('contextid' => $context->id, 'filearea' => 'folder_content', 'itemid' => 0);
        foreach ($files as $file) {
            $path = $file->get_filepath();
            if (stripos($path, '/backupdata/') === 0 or stripos($path, '/moddata/') === 0) {
                // do not publish protected data!
                continue;
            }
            $relpath = substr($path, strlen($directory) - 1);
            // keep only subfolder paths
            $file_record['filepath'] = $relpath;
            $fs->create_file_from_storedfile($file_record, $file);
        }
    }
    $candidates->close();
    // clear all course modinfo caches
    rebuild_course_cache(0, true);
}

/**
 * Upgrade code for the essay question type.
 * @param int $oldversion the version we are upgrading from.
 */
function xmldb_qtype_essay_upgrade($oldversion)
{
    global $CFG, $DB;
    $dbman = $DB->get_manager();
    // Moodle v2.2.0 release upgrade line
    // Put any upgrade step following this
    if ($oldversion < 2011102701) {
        $sql = "\n                  FROM {question} q\n                  JOIN {question_answers} qa ON qa.question = q.id\n\n                 WHERE q.qtype = 'essay'\n                   AND " . $DB->sql_isnotempty('question_answers', 'feedback', false, true);
        // In Moodle <= 2.0 essay had both question.generalfeedback and question_answers.feedback.
        // This was silly, and in Moodel >= 2.1 only question.generalfeedback. To avoid
        // dataloss, we concatenate question_answers.feedback onto the end of question.generalfeedback.
        $count = $DB->count_records_sql("\n                SELECT COUNT(1) {$sql}");
        if ($count) {
            $progressbar = new progress_bar('essay23', 500, true);
            $done = 0;
            $toupdate = $DB->get_recordset_sql("\n                    SELECT q.id,\n                           q.generalfeedback,\n                           q.generalfeedbackformat,\n                           qa.feedback,\n                           qa.feedbackformat\n                    {$sql}");
            foreach ($toupdate as $data) {
                $progressbar->update($done, $count, "Updating essay feedback ({$done}/{$count}).");
                upgrade_set_timeout(60);
                if ($data->generalfeedbackformat == $data->feedbackformat) {
                    $DB->set_field('question', 'generalfeedback', $data->generalfeedback . $data->feedback, array('id' => $data->id));
                } else {
                    $newdata = new stdClass();
                    $newdata->id = $data->id;
                    $newdata->generalfeedback = qtype_essay_convert_to_html($data->generalfeedback, $data->generalfeedbackformat) . qtype_essay_convert_to_html($data->feedback, $data->feedbackformat);
                    $newdata->generalfeedbackformat = FORMAT_HTML;
                    $DB->update_record('question', $newdata);
                }
            }
            $progressbar->update($count, $count, "Updating essay feedback complete!");
            $toupdate->close();
        }
        // Essay savepoint reached.
        upgrade_plugin_savepoint(true, 2011102701, 'qtype', 'essay');
    }
    if ($oldversion < 2011102702) {
        // Then we delete the old question_answers rows for essay questions.
        $DB->delete_records_select('question_answers', "question IN (SELECT id FROM {question} WHERE qtype = 'essay')");
        // Essay savepoint reached.
        upgrade_plugin_savepoint(true, 2011102702, 'qtype', 'essay');
    }
    // Moodle v2.3.0 release upgrade line
    // Put any upgrade step following this
    // Moodle v2.4.0 release upgrade line
    // Put any upgrade step following this
    return true;
}

/**
 * @package mod
 * @subpackage adobeconnect
 * @author Akinsaya Delamarre ([email protected])
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
function xmldb_adobeconnect_upgrade($oldversion = 0)
{
    global $CFG, $DB;
    $dbman = $DB->get_manager();
    //===== 1.9.0 upgrade line ======//
    if ($oldversion < 2010120800) {
        /// Define field introformat to be added to survey
        $table = new xmldb_table('adobeconnect');
        $field = new xmldb_field('introformat', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0', 'intro');
        /// Conditionally launch add field introformat
        if (!$dbman->field_exists($table, $field)) {
            $dbman->add_field($table, $field);
        }
        // conditionally migrate to html format in intro
        if ($CFG->texteditors !== 'textarea') {
            $rs = $DB->get_recordset('adobeconnect', array('introformat' => FORMAT_MOODLE), '', 'id,intro,introformat');
            foreach ($rs as $s) {
                $s->intro = text_to_html($s->intro, false, false, true);
                $s->introformat = FORMAT_HTML;
                $DB->update_record('adobeconnect', $s);
                upgrade_set_timeout();
            }
            $rs->close();
        }
        /// adobeconnect savepoint reached
        upgrade_mod_savepoint(true, 2010120800, 'adobeconnect');
    }
    if ($oldversion < 2011041400) {
        // Changing precision of field meeturl on table adobeconnect to (60)
        $table = new xmldb_table('adobeconnect');
        $field = new xmldb_field('meeturl', XMLDB_TYPE_CHAR, '60', null, null, null, null, 'templatescoid');
        // Launch change of precision for field meeturl
        $dbman->change_field_precision($table, $field);
        // adobeconnect savepoint reached
        upgrade_mod_savepoint(true, 2011041400, 'adobeconnect');
    }
    return true;
}

/**
 * Migrate geogebra package to new area if found
 *
 * @return
 */
function geogebra_migrate_files()
{
    global $CFG, $DB;
    $fs = get_file_storage();
    $sqlfrom = "FROM {geogebra} j\n                JOIN {modules} m ON m.name = 'geogebra'\n                JOIN {course_modules} cm ON (cm.module = m.id AND cm.instance = j.id)";
    $count = $DB->count_records_sql("SELECT COUNT('x') {$sqlfrom}");
    $rs = $DB->get_recordset_sql("SELECT j.id, j.url, j.course, cm.id AS cmid {$sqlfrom} ORDER BY j.course, j.id");
    if ($rs->valid()) {
        $pbar = new progress_bar('migrategeogebrafiles', 500, true);
        $i = 0;
        foreach ($rs as $geogebra) {
            $i++;
            upgrade_set_timeout(180);
            // set up timeout, may also abort execution
            $pbar->update($i, $count, "Migrating geogebra files - {$i}/{$count}.");
            $context = context_module::instance($geogebra->cmid);
            $coursecontext = context_course::instance($geogebra->course);
            if (!geogebra_is_valid_external_url($geogebra->url)) {
                // first copy local files if found - do not delete in case they are shared ;-)
                $geogebrafile = clean_param($geogebra->url, PARAM_PATH);
                $pathnamehash = sha1("/{$coursecontext->id}/course/legacy/0/{$geogebrafile}");
                if ($file = $fs->get_file_by_hash($pathnamehash)) {
                    $file_record = array('contextid' => $context->id, 'component' => 'mod_geogebra', 'filearea' => 'content', 'itemid' => 0, 'filepath' => '/');
                    try {
                        $fs->create_file_from_storedfile($file_record, $file);
                    } catch (Exception $x) {
                        // ignore any errors, we can not do much anyway
                    }
                    $geogebra->url = $pathnamehash;
                } else {
                    $geogebra->url = '';
                }
                $DB->update_record('geogebra', $geogebra);
            }
        }
    }
    $rs->close();
}

/**
 * Update all grades in gradebook.
 * @global object
 */
function forum_upgrade_grades() {
    global $DB;

    $sql = "SELECT COUNT('x')
              FROM {forum} f, {course_modules} cm, {modules} m
             WHERE m.name='forum' AND m.id=cm.module AND cm.instance=f.id";
    $count = $DB->count_records_sql($sql);

    $sql = "SELECT f.*, cm.idnumber AS cmidnumber, f.course AS courseid
              FROM {forum} f, {course_modules} cm, {modules} m
             WHERE m.name='forum' AND m.id=cm.module AND cm.instance=f.id";
    $rs = $DB->get_recordset_sql($sql);
    if ($rs->valid()) {
        $pbar = new progress_bar('forumupgradegrades', 500, true);
        $i=0;
        foreach ($rs as $forum) {
            $i++;
            upgrade_set_timeout(60*5); // set up timeout, may also abort execution
            forum_update_grades($forum, 0, false);
            $pbar->update($i, $count, "Updating Forum grades ($i/$count).");
        }
    }
    $rs->close();
}

/**
 * Migrate legacy files in intro and chapters
 * @return void
 */
function mod_giportfolio_migrate_all_areas()
{
    global $DB;
    $rsgiportfolios = $DB->get_recordset('giportfolio');
    foreach ($rsgiportfolios as $giportfolio) {
        upgrade_set_timeout(360);
        // Set up timeout, may also abort execution.
        $cm = get_coursemodule_from_instance('giportfolio', $giportfolio->id);
        $context = context_module::instance($cm->id);
        mod_giportfolio_migrate_area($giportfolio, 'intro', 'giportfolio', $giportfolio->course, $context, 'mod_giportfolio', 'intro', 0);
        $rschapters = $DB->get_recordset('giportfolio_chapters', array('giportfolioid' => $giportfolio->id));
        foreach ($rschapters as $chapter) {
            mod_giportfolio_migrate_area($chapter, 'content', 'giportfolio_chapters', $giportfolio->course, $context, 'mod_giportfolio', 'chapter', $chapter->id);
        }
        $rschapters->close();
    }
    $rsgiportfolios->close();
}

/**
 * Update all grades in gradebook.
 */
function assignment_upgrade_grades() {
    global $DB;

    $sql = "SELECT COUNT('x')
              FROM {assignment} a, {course_modules} cm, {modules} m
             WHERE m.name='assignment' AND m.id=cm.module AND cm.instance=a.id";
    $count = $DB->count_records_sql($sql);

    $sql = "SELECT a.*, cm.idnumber AS cmidnumber, a.course AS courseid
              FROM {assignment} a, {course_modules} cm, {modules} m
             WHERE m.name='assignment' AND m.id=cm.module AND cm.instance=a.id";
    $rs = $DB->get_recordset_sql($sql);
    if ($rs->valid()) {
        // too much debug output
        $pbar = new progress_bar('assignmentupgradegrades', 500, true);
        $i=0;
        foreach ($rs as $assignment) {
            $i++;
            upgrade_set_timeout(60*5); // set up timeout, may also abort execution
            assignment_update_grades($assignment);
            $pbar->update($i, $count, "Updating Assignment grades ($i/$count).");
        }
        upgrade_set_timeout(); // reset to default timeout
    }
    $rs->close();
}

/**
 * Update all grades in gradebook.
 *
 * @global object
 */
function data_upgrade_grades() {
    global $DB;

    $sql = "SELECT COUNT('x')
              FROM {data} d, {course_modules} cm, {modules} m
             WHERE m.name='data' AND m.id=cm.module AND cm.instance=d.id";
    $count = $DB->count_records_sql($sql);

    $sql = "SELECT d.*, cm.idnumber AS cmidnumber, d.course AS courseid
              FROM {data} d, {course_modules} cm, {modules} m
             WHERE m.name='data' AND m.id=cm.module AND cm.instance=d.id";
    $rs = $DB->get_recordset_sql($sql);
    if ($rs->valid()) {
        // too much debug output
        $pbar = new progress_bar('dataupgradegrades', 500, true);
        $i=0;
        foreach ($rs as $data) {
            $i++;
            upgrade_set_timeout(60*5); // set up timeout, may also abort execution
            data_update_grades($data, 0, false);
            $pbar->update($i, $count, "Updating Database grades ($i/$count).");
        }
    }
    $rs->close();
}

/**
 * Main upgrade tasks to be executed on Moodle version bump
 *
 * This function is automatically executed after one bump in the Moodle core
 * version is detected. It's in charge of performing the required tasks
 * to raise core from the previous version to the next one.
 *
 * It's a collection of ordered blocks of code, named "upgrade steps",
 * each one performing one isolated (from the rest of steps) task. Usually
 * tasks involve creating new DB objects or performing manipulation of the
 * information for cleanup/fixup purposes.
 *
 * Each upgrade step has a fixed structure, that can be summarised as follows:
 *
 * if ($oldversion < XXXXXXXXXX.XX) {
 *     // Explanation of the update step, linking to issue in the Tracker if necessary
 *     upgrade_set_timeout(XX); // Optional for big tasks
 *     // Code to execute goes here, usually the XMLDB Editor will
 *     // help you here. See {@link http://docs.moodle.org/dev/XMLDB_editor}.
 *     upgrade_main_savepoint(true, XXXXXXXXXX.XX);
 * }
 *
 * All plugins within Moodle (modules, blocks, reports...) support the existence of
 * their own upgrade.php file, using the "Frankenstyle" component name as
 * defined at {@link http://docs.moodle.org/dev/Frankenstyle}, for example:
 *     - {@link xmldb_page_upgrade($oldversion)}. (modules don't require the plugintype ("mod_") to be used.
 *     - {@link xmldb_auth_manual_upgrade($oldversion)}.
 *     - {@link xmldb_workshopform_accumulative_upgrade($oldversion)}.
 *     - ....
 *
 * In order to keep the contents of this file reduced, it's allowed to create some helper
 * functions to be used here in the {@link upgradelib.php} file at the same directory. Note
 * that such a file must be manually included from upgrade.php, and there are some restrictions
 * about what can be used within it.
 *
 * For more information, take a look to the documentation available:
 *     - Data definition API: {@link http://docs.moodle.org/dev/Data_definition_API}
 *     - Upgrade API: {@link http://docs.moodle.org/dev/Upgrade_API}
 *
 * @param int $oldversion
 * @return bool always true
 */
function xmldb_main_upgrade($oldversion)
{
    global $CFG, $USER, $DB, $OUTPUT, $SITE;
    require_once $CFG->libdir . '/db/upgradelib.php';
    // Core Upgrade-related functions
    $dbman = $DB->get_manager();
    // loads ddl manager and xmldb classes
    if ($oldversion < 2011120500) {
        // just in case somebody hacks upgrade scripts or env, we really can not continue
        echo "You need to upgrade to 2.2.x first!\n";
        exit(1);
        // Note this savepoint is 100% unreachable, but needed to pass the upgrade checks
        upgrade_main_savepoint(true, 2011120500);
    }
    // Moodle v2.2.0 release upgrade line
    // Put any upgrade step following this
    if ($oldversion < 2011120500.02) {
        upgrade_set_timeout(60 * 20);
        // This may take a while
        // MDL-28180. Some missing restrictions in certain backup & restore operations
        // were causing incorrect duplicates in the course_completion_aggr_methd table.
        // This upgrade step takes rid of them.
        $sql = 'SELECT course, criteriatype, MIN(id) AS minid
                  FROM {course_completion_aggr_methd}
              GROUP BY course, criteriatype
                HAVING COUNT(*) > 1';
        $duprs = $DB->get_recordset_sql($sql);
        foreach ($duprs as $duprec) {
            // We need to handle NULLs in criteriatype diferently
            if (is_null($duprec->criteriatype)) {
                $where = 'course = ? AND criteriatype IS NULL AND id > ?';
                $params = array($duprec->course, $duprec->minid);
            } else {
                $where = 'course = ? AND criteriatype = ? AND id > ?';
                $params = array($duprec->course, $duprec->criteriatype, $duprec->minid);
            }
            $DB->delete_records_select('course_completion_aggr_methd', $where, $params);
        }
        $duprs->close();
        // Main savepoint reached
        upgrade_main_savepoint(true, 2011120500.02);
    }
    if ($oldversion < 2011120500.03) {
        // Changing precision of field value on table user_preferences to (1333)
        $table = new xmldb_table('user_preferences');
        $field = new xmldb_field('value', XMLDB_TYPE_CHAR, '1333', null, XMLDB_NOTNULL, null, null, 'name');
        // Launch change of precision for field value
        $dbman->change_field_precision($table, $field);
        // Main savepoint reached
        upgrade_main_savepoint(true, 2011120500.03);
    }
    if ($oldversion < 2012020200.03) {
        // Define index rolecontext (not unique) to be added to role_assignments
        $table = new xmldb_table('role_assignments');
        $index = new xmldb_index('rolecontext', XMLDB_INDEX_NOTUNIQUE, array('roleid', 'contextid'));
        // Conditionally launch add index rolecontext
        if (!$dbman->index_exists($table, $index)) {
            $dbman->add_index($table, $index);
//.........这里部分代码省略.........

/**
 * This file keeps track of upgrades to
 * the forum module
 *
 * Sometimes, changes between versions involve
 * alterations to database structures and other
 * major things that may break installations.
 *
 * The upgrade function in this file will attempt
 * to perform all the necessary actions to upgrade
 * your older installation to the current version.
 *
 * If there's something it cannot do itself, it
 * will tell you what you need to do.
 *
 * The commands in here will all be database-neutral,
 * using the methods of database_manager class
 *
 * Please do not forget to use upgrade_set_timeout()
 * before any action that may take longer time to finish.
 *
 * @package mod-forum
 * @copyright 2003 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
function xmldb_forum_upgrade($oldversion)
{
    global $CFG, $DB, $OUTPUT;
    $dbman = $DB->get_manager();
    // loads ddl manager and xmldb classes
    //===== 1.9.0 upgrade line ======//
    if ($oldversion < 2007101511) {
        //MDL-13866 - send forum ratins to gradebook again
        require_once $CFG->dirroot . '/mod/forum/lib.php';
        forum_upgrade_grades();
        upgrade_mod_savepoint(true, 2007101511, 'forum');
    }
    if ($oldversion < 2008072800) {
        /// Define field completiondiscussions to be added to forum
        $table = new xmldb_table('forum');
        $field = new xmldb_field('completiondiscussions');
        $field->set_attributes(XMLDB_TYPE_INTEGER, '9', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0', 'blockperiod');
        /// Launch add field completiondiscussions
        if (!$dbman->field_exists($table, $field)) {
            $dbman->add_field($table, $field);
        }
        $field = new xmldb_field('completionreplies');
        $field->set_attributes(XMLDB_TYPE_INTEGER, '9', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0', 'completiondiscussions');
        /// Launch add field completionreplies
        if (!$dbman->field_exists($table, $field)) {
            $dbman->add_field($table, $field);
        }
        /// Define field completionposts to be added to forum
        $field = new xmldb_field('completionposts');
        $field->set_attributes(XMLDB_TYPE_INTEGER, '9', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0', 'completionreplies');
        /// Launch add field completionposts
        if (!$dbman->field_exists($table, $field)) {
            $dbman->add_field($table, $field);
        }
        upgrade_mod_savepoint(true, 2008072800, 'forum');
    }
    if ($oldversion < 2008081900) {
        /////////////////////////////////////
        /// new file storage upgrade code ///
        /////////////////////////////////////
        $fs = get_file_storage();
        $empty = $DB->sql_empty();
        // silly oracle empty string handling workaround
        $sqlfrom = "FROM {forum_posts} p\n                    JOIN {forum_discussions} d ON d.id = p.discussion\n                    JOIN {forum} f ON f.id = d.forum\n                    JOIN {modules} m ON m.name = 'forum'\n                    JOIN {course_modules} cm ON (cm.module = m.id AND cm.instance = f.id)\n                   WHERE p.attachment <> '{$empty}' AND p.attachment <> '1'";
        $count = $DB->count_records_sql("SELECT COUNT('x') {$sqlfrom}");
        $rs = $DB->get_recordset_sql("SELECT p.id, p.attachment, p.userid, d.forum, f.course, cm.id AS cmid {$sqlfrom} ORDER BY f.course, f.id, d.id");
        if ($rs->valid()) {
            $pbar = new progress_bar('migrateforumfiles', 500, true);
            $i = 0;
            foreach ($rs as $post) {
                $i++;
                upgrade_set_timeout(60);
                // set up timeout, may also abort execution
                $pbar->update($i, $count, "Migrating forum posts - {$i}/{$count}.");
                $filepath = "{$CFG->dataroot}/{$post->course}/{$CFG->moddata}/forum/{$post->forum}/{$post->id}/{$post->attachment}";
                if (!is_readable($filepath)) {
                    //file missing??
                    echo $OUTPUT->notification("File not readable, skipping: " . $filepath);
                    $post->attachment = '';
                    $DB->update_record('forum_posts', $post);
                    continue;
                }
                $context = get_context_instance(CONTEXT_MODULE, $post->cmid);
                $filearea = 'attachment';
                $filename = clean_param($post->attachment, PARAM_FILE);
                if ($filename === '') {
                    echo $OUTPUT->notification("Unsupported post filename, skipping: " . $filepath);
                    $post->attachment = '';
                    $DB->update_record('forum_posts', $post);
                    continue;
                }
                if (!$fs->file_exists($context->id, 'mod_forum', $filearea, $post->id, '/', $filename)) {
                    $file_record = array('contextid' => $context->id, 'component' => 'mod_forum', 'filearea' => $filearea, 'itemid' => $post->id, 'filepath' => '/', 'filename' => $filename, 'userid' => $post->userid);
                    if ($fs->create_file_from_pathname($file_record, $filepath)) {
                        $post->attachment = '1';
//.........这里部分代码省略.........

function xmldb_chat_upgrade($oldversion)
{
    global $CFG, $DB;
    $dbman = $DB->get_manager();
    //===== 1.9.0 upgrade line ======//
    if ($oldversion < 2010050100) {
        /// Changing precision of field ip on table chat_users to (45)
        $table = new xmldb_table('chat_users');
        $field = new xmldb_field('ip', XMLDB_TYPE_CHAR, '45', null, XMLDB_NOTNULL, null, null, 'version');
        /// Launch change of precision for field ip
        $dbman->change_field_precision($table, $field);
        /// chat savepoint reached
        upgrade_mod_savepoint(true, 2010050100, 'chat');
    }
    if ($oldversion < 2010050101) {
        /// Define field introformat to be added to chat
        $table = new xmldb_table('chat');
        $field = new xmldb_field('introformat', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0', 'intro');
        /// Launch add field introformat
        if (!$dbman->field_exists($table, $field)) {
            $dbman->add_field($table, $field);
        }
        // conditionally migrate to html format in intro
        if ($CFG->texteditors !== 'textarea') {
            $rs = $DB->get_recordset('chat', array('introformat' => FORMAT_MOODLE), '', 'id,intro,introformat');
            foreach ($rs as $ch) {
                $ch->intro = text_to_html($ch->intro, false, false, true);
                $ch->introformat = FORMAT_HTML;
                $DB->update_record('chat', $ch);
                upgrade_set_timeout();
            }
            $rs->close();
        }
        /// chat savepoint reached
        upgrade_mod_savepoint(true, 2010050101, 'chat');
    }
    /// Creating chat_messages_current to hold latest chat messages
    if ($oldversion < 2010050102) {
        /// Define table chat_messages_current to be created
        $table = new xmldb_table('chat_messages_current');
        /// Adding fields to table chat_messages_current
        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
        $table->add_field('chatid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
        $table->add_field('userid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
        $table->add_field('groupid', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
        $table->add_field('system', XMLDB_TYPE_INTEGER, '1', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0');
        $table->add_field('message', XMLDB_TYPE_TEXT, 'small', null, XMLDB_NOTNULL, null, null);
        $table->add_field('timestamp', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, '0');
        /// Adding keys to table chat_messages_current
        $table->add_key('primary', XMLDB_KEY_PRIMARY, array('id'));
        $table->add_key('chatid', XMLDB_KEY_FOREIGN, array('chatid'), 'chat', array('id'));
        /// Adding indexes to table chat_messages_current
        $table->add_index('userid', XMLDB_INDEX_NOTUNIQUE, array('userid'));
        $table->add_index('groupid', XMLDB_INDEX_NOTUNIQUE, array('groupid'));
        $table->add_index('timestamp-chatid', XMLDB_INDEX_NOTUNIQUE, array('timestamp', 'chatid'));
        /// create table for chat_messages_current
        if (!$dbman->table_exists($table)) {
            $dbman->create_table($table);
        }
        /// chat savepoint reached
        upgrade_mod_savepoint(true, 2010050102, 'chat');
    }
    // Moodle v2.1.0 release upgrade line
    // Put any upgrade step following this
    return true;
}

/**
 * Main upgrade tasks to be executed on Moodle version bump
 *
 * This function is automatically executed after one bump in the Moodle core
 * version is detected. It's in charge of performing the required tasks
 * to raise core from the previous version to the next one.
 *
 * It's a collection of ordered blocks of code, named "upgrade steps",
 * each one performing one isolated (from the rest of steps) task. Usually
 * tasks involve creating new DB objects or performing manipulation of the
 * information for cleanup/fixup purposes.
 *
 * Each upgrade step has a fixed structure, that can be summarised as follows:
 *
 * if ($oldversion < XXXXXXXXXX.XX) {
 *     // Explanation of the update step, linking to issue in the Tracker if necessary
 *     upgrade_set_timeout(XX); // Optional for big tasks
 *     // Code to execute goes here, usually the XMLDB Editor will
 *     // help you here. See {@link http://docs.moodle.org/dev/XMLDB_editor}.
 *     upgrade_main_savepoint(true, XXXXXXXXXX.XX);
 * }
 *
 * All plugins within Moodle (modules, blocks, reports...) support the existence of
 * their own upgrade.php file, using the "Frankenstyle" component name as
 * defined at {@link http://docs.moodle.org/dev/Frankenstyle}, for example:
 *     - {@link xmldb_page_upgrade($oldversion)}. (modules don't require the plugintype ("mod_") to be used.
 *     - {@link xmldb_auth_manual_upgrade($oldversion)}.
 *     - {@link xmldb_workshopform_accumulative_upgrade($oldversion)}.
 *     - ....
 *
 * In order to keep the contents of this file reduced, it's allowed to create some helper
 * functions to be used here in the {@link upgradelib.php} file at the same directory. Note
 * that such a file must be manually included from upgrade.php, and there are some restrictions
 * about what can be used within it.
 *
 * For more information, take a look to the documentation available:
 *     - Data definition API: {@link http://docs.moodle.org/dev/Data_definition_API}
 *     - Upgrade API: {@link http://docs.moodle.org/dev/Upgrade_API}
 *
 * @param int $oldversion
 * @return bool always true
 */
function xmldb_main_upgrade($oldversion)
{
    global $CFG, $USER, $DB, $OUTPUT, $SITE, $COURSE;
    require_once $CFG->libdir . '/db/upgradelib.php';
    // Core Upgrade-related functions
    $dbman = $DB->get_manager();
    // loads ddl manager and xmldb classes
    if ($oldversion < 2011120500) {
        // just in case somebody hacks upgrade scripts or env, we really can not continue
        echo "You need to upgrade to 2.2.x first!\n";
        exit(1);
        // Note this savepoint is 100% unreachable, but nee