moodle-mod_attendance/db/upgrade.php

<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * upgrade processes for this module.
 *
 * @package   mod_attendance
 * @copyright 2011 Artem Andreev <andreev.artem@gmail.com>
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/**
 * upgrade this attendance instance - this function could be skipped but it will be needed later
 * @param int $oldversion The old version of the attendance module
 * @return bool
 */
function xmldb_attendance_upgrade($oldversion=0) {

    global $CFG, $THEME, $DB;
    $dbman = $DB->get_manager(); // Loads ddl manager and xmldb classes.

    $result = true;

    if ($oldversion < 2013082902) {
        // Replace values that reference old module "attforblock" to "attendance".
        $sql = "UPDATE {grade_items}
                   SET itemmodule = 'attendance'
                 WHERE itemmodule = 'attforblock'";

        $DB->execute($sql);

        $sql = "UPDATE {grade_items_history}
                   SET itemmodule = 'attendance'
                 WHERE itemmodule = 'attforblock'";

        $DB->execute($sql);

        /*
         * The user's custom capabilities need to be preserved due to the module renaming.
         * Capabilities with a modifierid = 0 value are installed by default.
         * Only update the user's custom capabilities where modifierid is not zero.
         */
        $sql = $DB->sql_like('capability', '?').' AND modifierid <> 0';
        $rs = $DB->get_recordset_select('role_capabilities', $sql, array('%mod/attforblock%'));
        foreach ($rs as $cap) {
            $renamedcapability = str_replace('mod/attforblock', 'mod/attendance', $cap->capability);
            $exists = $DB->record_exists('role_capabilities', array('roleid' => $cap->roleid, 'capability' => $renamedcapability));
            if (!$exists) {
                $DB->update_record('role_capabilities', array('id' => $cap->id, 'capability' => $renamedcapability));
            }
        }

        // Delete old role capabilities.
        $sql = $DB->sql_like('capability', '?');
        $DB->delete_records_select('role_capabilities', $sql, array('%mod/attforblock%'));

        // Delete old capabilities.
        $DB->delete_records_select('capabilities', 'component = ?', array('mod_attforblock'));

        upgrade_plugin_savepoint($result, 2013082902, 'mod', 'attendance');
    }

    return $result;
}