PHP index_exists函数代码示例

function xmldb_taoresource_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
    ///     $result = result of "/lib/ddllib.php" function calls
    /// }
    //===== 1.9.0 upgrade line ======//
    // change the remoteid key to be non-unique
    if ($result && $oldversion < 2007101510) {
        $table = new XMLDBTable('taoresource_entry');
        $index = new XMLDBIndex('remoteid');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('remoteid'));
        if (index_exists($table, $index)) {
            $result = $result && drop_index($table, $index);
        }
        $result = $result && add_index($table, $index);
    }
    // change the remoteid key to be non-unique
    if ($result && $oldversion < 2007101511) {
        $table = new XMLDBTable('taoresource_metadata');
        $field = new XMLDBField('entry_id');
        // change the field type from ext to int
        if (field_exists($table, $field)) {
            $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'id');
            $result = $result && change_field_type($table, $field);
        }
    }
    return $result;
}

/**
 * This function will rename the index in the table passed as arguments
 * Before renaming the index, the function will check it exists
 * Experimental. Shouldn't be used at all!
 *
 * @uses $CFG, $db
 * @param XMLDBTable table object (just the name is mandatory)
 * @param XMLDBIndex index object (full specs are required)
 * @param string new name of the index
 * @param boolean continue to specify if must continue on error (true) or stop (false)
 * @param boolean feedback to specify to show status info (true) or not (false)
 * @return boolean true on success, false on error
 */
function rename_index($table, $index, $newname, $continue = true, $feedback = true)
{
    global $CFG, $db;
    debugging('rename_index() is one experimental feature. You must not use it in production!', DEBUG_DEVELOPER);
    $status = true;
    if (strtolower(get_class($table)) != 'xmldbtable') {
        return false;
    }
    if (strtolower(get_class($index)) != 'xmldbindex') {
        return false;
    }
    /// Check index exists
    if (!index_exists($table, $index)) {
        debugging('Index ' . $table->getName() . '->' . $index->getName() . ' does not exist. Rename skipped', DEBUG_DEVELOPER);
        return true;
        //Index doesn't exist, nothing to do
    }
    /// Check newname isn't empty
    if (!$newname) {
        debugging('New name for index ' . $table->getName() . '->' . $index->getName() . ' is empty! Rename skipped', DEBUG_DEVELOPER);
        return true;
        //Index doesn't exist, nothing to do
    }
    if (!($sqlarr = $table->getRenameIndexSQL($CFG->dbtype, $CFG->prefix, $index, $newname, false))) {
        debugging('Some DBs do not support index renaming (MySQL). Rename skipped', DEBUG_DEVELOPER);
        return true;
        //Empty array = nothing to do = no error
    }
    return execute_sql_arr($sqlarr, $continue, $feedback);
}

function xmldb_data_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
    ///     $result = result of "/lib/ddllib.php" function calls
    /// }
    if ($result && $oldversion < 2006121300) {
        /// Define field format to be added to data_comments
        $table = new XMLDBTable('data_comments');
        $field = new XMLDBField('format');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '2', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'content');
        /// Launch add field format
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2007022600) {
        /// Define field asearchtemplate to be added to data
        $table = new XMLDBTable('data');
        $field = new XMLDBField('asearchtemplate');
        $field->setAttributes(XMLDB_TYPE_TEXT, 'small', null, null, null, null, null, null, 'jstemplate');
        /// Launch add field asearchtemplate
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2007072200) {
        require_once $CFG->dirroot . '/mod/data/lib.php';
        // too much debug output
        $db->debug = false;
        data_update_grades();
        $db->debug = true;
    }
    if ($result && $oldversion < 2007081400) {
        /// Define field notification to be added to data
        $table = new XMLDBTable('data');
        $field = new XMLDBField('notification');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '10', null, null, null, null, null, null, 'editany');
        /// Launch add field notification
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2007081402) {
        /// Define index type-dataid (not unique) to be added to data_fields
        $table = new XMLDBTable('data_fields');
        $index = new XMLDBIndex('type-dataid');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('type', 'dataid'));
        /// Launch add index type-dataid
        if (!index_exists($table, $index)) {
            $result = $result && add_index($table, $index);
        }
        /// Define index course (not unique) to be added to data
        $table = new XMLDBTable('data');
        $index = new XMLDBIndex('course');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('course'));
        /// Launch add index course
        if (!index_exists($table, $index)) {
            $result = $result && add_index($table, $index);
        }
    }
    //===== 1.9.0 upgrade line ======//
    if ($result && $oldversion < 2007101512) {
        /// Launch add field asearchtemplate again if does not exists yet - reported on several sites
        $table = new XMLDBTable('data');
        $field = new XMLDBField('asearchtemplate');
        $field->setAttributes(XMLDB_TYPE_TEXT, 'small', null, null, null, null, null, null, 'jstemplate');
        if (!field_exists($table, $field)) {
            $result = $result && add_field($table, $field);
        }
    }
    return $result;
}

function post_check_15()
{
    global $dbh;
    if (!index_exists("maia_mail", "maia_mail_idx_subject")) {
        return array(false, "Index maia_mail_idx_subject doesn't exist");
    } else {
        return array(true, "");
    }
}

//.........这里部分代码省略.........
        $cron->callfunction = 'export_cleanup_old_exports';
        $cron->minute = '0';
        $cron->hour = '3,13';
        $cron->day = '*';
        $cron->month = '*';
        $cron->dayofweek = '*';
        insert_record('cron', $cron);
    }
    if ($oldversion < 2009070600) {
        // This was forgotten as part of the 1.0 -> 1.1 upgrade
        if ($data = check_upgrades('blocktype.file/html')) {
            upgrade_plugin($data);
        }
    }
    if ($oldversion < 2009070700) {
        foreach (array('addfriend', 'removefriend', 'addfriendrequest', 'removefriendrequest') as $eventtype) {
            $event = (object) array('name' => $eventtype);
            ensure_record_exists('event_type', $event, $event);
        }
    }
    if ($oldversion < 2009070900) {
        if (is_mysql()) {
            execute_sql("ALTER TABLE {usr} DROP FOREIGN KEY {usr_las_fk}");
            execute_sql("ALTER TABLE {usr} DROP INDEX {usr_las_ix}");
        }
        $table = new XMLDBTable('usr');
        $field = new XMLDBField('lastauthinstance');
        drop_field($table, $field);
    }
    if ($oldversion < 2009080600) {
        $table = new XMLDBTable('view');
        $index = new XMLDBIndex('view_own_type_uix');
        $index->setAttributes(XMLDB_INDEX_UNIQUE, array('owner'));
        if (!index_exists($table, $index)) {
            // Delete duplicate profile views if there are any, then add an index
            // that will prevent it happening again - but only on postgres, as it's
            // the only db that supports partial indexes
            if ($viewdata = get_records_sql_array("\n                SELECT owner, id\n                FROM {view}\n                WHERE owner IN (\n                    SELECT owner\n                    FROM {view}\n                    WHERE type = 'profile'\n                    GROUP BY owner\n                    HAVING COUNT(*) > 1\n                )\n                AND type = 'profile'\n                ORDER BY owner, id", array())) {
                require_once 'view.php';
                $seen = array();
                foreach ($viewdata as $record) {
                    $seen[$record->owner][] = $record->id;
                }
                foreach ($seen as $owner => $views) {
                    // Remove the first one, which is their real profile view
                    array_shift($views);
                    foreach ($views as $viewid) {
                        delete_records('artefact_feedback', 'view', $viewid);
                        delete_records('view_feedback', 'view', $viewid);
                        delete_records('view_access', 'view', $viewid);
                        delete_records('view_access_group', 'view', $viewid);
                        delete_records('view_access_usr', 'view', $viewid);
                        delete_records('view_access_token', 'view', $viewid);
                        delete_records('view_autocreate_grouptype', 'view', $viewid);
                        delete_records('view_tag', 'view', $viewid);
                        delete_records('usr_watchlist_view', 'view', $viewid);
                        if ($blockinstanceids = get_column('block_instance', 'id', 'view', $viewid)) {
                            foreach ($blockinstanceids as $id) {
                                if (table_exists(new XMLDBTable('blocktype_wall_post'))) {
                                    delete_records('blocktype_wall_post', 'instance', $id);
                                }
                                delete_records('view_artefact', 'block', $id);
                                delete_records('block_instance', 'id', $id);
                            }
                        }
                        delete_records('view', 'id', $viewid);

/**
 * @package   turnitintool
 * @copyright 2012 Turnitin
 */
function xmldb_turnitintool_upgrade($oldversion)
{
    global $CFG, $THEME, $DB, $OUTPUT;
    $result = true;
    // Do necessary DB upgrades here
    //function add_field($name, $type, $precision=null, $unsigned=null, $notnull=null, $sequence=null, $enum=null, $enumvalues=null, $default=null, $previous=null)
    // Newer DB Man ($name, $type=null, $precision=null, $unsigned=null, $notnull=null, $sequence=null, $default=null, $previous=null)
    if ($result && $oldversion < 2009071501) {
        if (is_callable(array($DB, 'get_manager'))) {
            $dbman = $DB->get_manager();
            $table = new xmldb_table('turnitintool_submissions');
            $field = new xmldb_field('submission_gmimaged', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'submission_grade');
            if (!$dbman->field_exists($table, $field)) {
                $dbman->add_field($table, $field);
            }
        } else {
            $table = new XMLDBTable('turnitintool_submissions');
            $field = new XMLDBField('submission_gmimaged');
            $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'submission_grade');
            $result = $result && add_field($table, $field);
        }
    }
    if ($result && $oldversion < 2009091401) {
        if (is_callable(array($DB, 'get_manager'))) {
            $dbman = $DB->get_manager();
            $table = new xmldb_table('turnitintool');
            $field = new xmldb_field('introformat', XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, null, null, null, null, '0', 'intro');
            if (!$dbman->field_exists($table, $field)) {
                $dbman->add_field($table, $field);
            }
        } else {
            $table = new XMLDBTable('turnitintool');
            $field = new XMLDBField('introformat');
            $field->setAttributes(XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, null, null, null, null, '0', 'intro');
            $result = $result && add_field($table, $field);
        }
    }
    if ($result && $oldversion < 2009092901) {
        if (is_callable(array($DB, 'get_manager'))) {
            $dbman = $DB->get_manager();
            $table1 = new xmldb_table('turnitintool');
            $field1 = new xmldb_field('resubmit', XMLDB_TYPE_INTEGER, '1', XMLDB_UNSIGNED, null, null, null, null, '0', 'defaultdtpost');
            if ($dbman->field_exists($table1, $field1)) {
                $dbman->rename_field($table1, $field1, 'anon');
            }
            $table2 = new xmldb_table('turnitintool_submissions');
            $field2 = new xmldb_field('submission_unanon', XMLDB_TYPE_INTEGER, '1', XMLDB_UNSIGNED, NULL, null, null, null, '0', 'submission_nmlastname');
            $field3 = new xmldb_field('submission_unanonreason', XMLDB_TYPE_TEXT, 'medium', null, null, null, null, 'submission_unanon');
            $field4 = new xmldb_field('submission_nmuserid', XMLDB_TYPE_TEXT, 'medium', null, null, null, null, null);
            if (!$dbman->field_exists($table2, $field2)) {
                $dbman->add_field($table2, $field2);
            }
            if (!$dbman->field_exists($table2, $field3)) {
                $dbman->add_field($table2, $field3);
            }
            $dbman->change_field_type($table2, $field4);
        } else {
            $table1 = new XMLDBTable('turnitintool');
            $field1 = new XMLDBField('resubmit');
            $field1->setAttributes(XMLDB_TYPE_INTEGER, '1', XMLDB_UNSIGNED, null, null, null, null, '0', 'defaultdtpost');
            $result = $result && rename_field($table1, $field1, 'anon');
            $table2 = new XMLDBTable('turnitintool_submissions');
            $field2 = new XMLDBField('submission_unanon');
            $field3 = new XMLDBField('submission_unanonreason');
            $field4 = new XMLDBField('submission_nmuserid');
            $field2->setAttributes(XMLDB_TYPE_INTEGER, '1', XMLDB_UNSIGNED, null, null, null, null, '0', 'submission_nmlastname');
            $result = $result && add_field($table2, $field2);
            $field3->setAttributes(XMLDB_TYPE_TEXT, 'medium', null, null, null, null, null, null, 'submission_unanon');
            $result = $result && add_field($table2, $field3);
            $field4->setAttributes(XMLDB_TYPE_TEXT, 'medium', null, null, null, null, null, null, null);
            $result = $result && change_field_type($table2, $field4);
        }
    }
    if ($result && $oldversion < 2009120501) {
        if (is_callable(array($DB, 'get_manager'))) {
            $dbman = $DB->get_manager();
            // Launch add index userid
            $table = new xmldb_table('turnitintool_submissions');
            $index = new xmldb_index('userid', XMLDB_INDEX_NOTUNIQUE, array('userid'));
            if (!$dbman->index_exists($table, $index)) {
                $dbman->add_index($table, $index);
            }
            // Launch add index turnitintoolid
            $table = new xmldb_table('turnitintool_submissions');
            $index = new xmldb_index('turnitintoolid', XMLDB_INDEX_NOTUNIQUE, array('turnitintoolid'));
            if (!$dbman->index_exists($table, $index)) {
                $dbman->add_index($table, $index);
            }
        } else {
            $table = new XMLDBTable('turnitintool_submissions');
            // Launch add index userid
            $index = new XMLDBIndex('userid');
            $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('userid'));
            if (index_exists($table, $index)) {
                $result = $result && add_index($table, $index);
            }
//.........这里部分代码省略.........

function xmldb_data_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
    ///     $result = result of "/lib/ddllib.php" function calls
    /// }
    if ($result && $oldversion < 2006121300) {
        /// Define field format to be added to data_comments
        $table = new XMLDBTable('data_comments');
        $field = new XMLDBField('format');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '2', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'content');
        /// Launch add field format
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2007022600) {
        /// Define field asearchtemplate to be added to data
        $table = new XMLDBTable('data');
        $field = new XMLDBField('asearchtemplate');
        $field->setAttributes(XMLDB_TYPE_TEXT, 'small', null, null, null, null, null, null, 'jstemplate');
        /// Launch add field asearchtemplate
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2007072200) {
        require_once $CFG->dirroot . '/mod/data/lib.php';
        // too much debug output
        $db->debug = false;
        data_update_grades();
        $db->debug = true;
    }
    if ($result && $oldversion < 2007081400) {
        /// Define field notification to be added to data
        $table = new XMLDBTable('data');
        $field = new XMLDBField('notification');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '10', null, null, null, null, null, null, 'editany');
        /// Launch add field notification
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2007081402) {
        /// Define index type-dataid (not unique) to be added to data_fields
        $table = new XMLDBTable('data_fields');
        $index = new XMLDBIndex('type-dataid');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('type', 'dataid'));
        /// Launch add index type-dataid
        if (!index_exists($table, $index)) {
            $result = $result && add_index($table, $index);
        }
        /// Define index course (not unique) to be added to data
        $table = new XMLDBTable('data');
        $index = new XMLDBIndex('course');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('course'));
        /// Launch add index course
        if (!index_exists($table, $index)) {
            $result = $result && add_index($table, $index);
        }
    }
    //===== 1.9.0 upgrade line ======//
    if ($result && $oldversion < 2007101512) {
        /// Launch add field asearchtemplate again if does not exists yet - reported on several sites
        $table = new XMLDBTable('data');
        $field = new XMLDBField('asearchtemplate');
        $field->setAttributes(XMLDB_TYPE_TEXT, 'small', null, null, null, null, null, null, 'jstemplate');
        if (!field_exists($table, $field)) {
            $result = $result && add_field($table, $field);
        }
    }
    ///Display a warning message about "Required Entries" fix from MDL-16999
    if ($result && $oldversion < 2007101514) {
        if (!get_config('data', 'requiredentriesfixflag')) {
            set_config('requiredentriesfixflag', true, 'data');
            // remove old flag
            $databases = get_records_sql("SELECT d.*, c.fullname\n                                              FROM {$CFG->prefix}data d, {$CFG->prefix}course c\n                                              WHERE d.course = c.id\n                                              AND (d.requiredentries > 0 OR d.requiredentriestoview > 0)\n                                              ORDER BY c.fullname, d.name");
            if (!empty($databases)) {
                $a = new object();
                $a->text = '';
                foreach ($databases as $database) {
                    $a->text .= "<p>" . $database->fullname . " - " . $database->name . " (course id: " . $database->course . " - database id: " . $database->id . ")</p>";
                }
                notify(get_string('requiredentrieschanged', 'data', $a));
            }
        }
    }
    if ($result && $oldversion < 2007101515) {
        // Upgrade all the data->notification currently being
        // NULL to 0
        $sql = "UPDATE {$CFG->prefix}data SET notification=0 WHERE notification IS NULL";
        $result = execute_sql($sql);
        $table = new XMLDBTable('data');
        $field = new XMLDBField('notification');
        // First step, Set NOT NULL
        $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'editany');
        $result = $result && change_field_notnull($table, $field);
        // Second step, Set default to 0
        $result = $result && change_field_default($table, $field);
    }
    return $result;
//.........这里部分代码省略.........

	

	<br>
	<?php 
    echo '<br>';
    /********* Start warnings for existing files. *********/
    if (wordpress_exists() === true) {
        pb_backupbuddy::alert('WARNING: Existing WordPress installation found. It is strongly recommended that existing WordPress files and database be removed prior to migrating or restoring to avoid conflicts. You should not install WordPress prior to migrating.');
    }
    if (phpini_exists() === true) {
        pb_backupbuddy::alert('WARNING: Existing php.ini file found. If your backup also contains a php.ini file it may overwrite the current one, possibly resulting in changes in cofiguration or problems. Make a backup of your existing file if your are unsure.');
    }
    if (htaccess_exists() === true) {
        pb_backupbuddy::alert('WARNING: Existing .htaccess file found. If your backup also contains a .htaccess file it may overwrite the current one, possibly resulting in changed in configuration or problems. Make a backup of your existing file if you are unsure.');
    }
    if (index_exists() === true) {
        pb_backupbuddy::alert('WARNING: A default page to load (index.htm/html) was found in the site root. This may prevent WordPress from loading depending on server configuration.   Deleting this default index.htm/index.html file before or after restoring will resolve the issue if encountered.');
    }
    /********* End warnings for existing files. *********/
    // If one or more backup files was found then provide a button to continue.
    if (!empty($backup_archives)) {
        echo '</div><!-- /wrap -->';
        echo '<div class="main_box_foot">';
        echo '<input type="submit" name="submit" value="Next Step &rarr;" class="button">';
        echo '</div>';
    } else {
        //pb_backupbuddy::alert( 'Upload a backup file to continue.' );
        echo '<b>You must upload a backup file by FTP, the upload tab, or import from Stash to continue.</b>';
        echo '</div><!-- /wrap -->';
    }
    echo '</form>';

/**
 * on the install we still need to index the text description
 * which the install.xml syntax does not let us do in a database
 * dependent fashion
 */
function taoresource_install()
{
    global $CFG;
    $result = true;
    if (preg_match('/^postgres/', $CFG->dbtype)) {
        $idx_field = 'description';
    } else {
        $idx_field = 'description(1000)';
    }
    $table = new XMLDBTable('taoresource_entry');
    $index = new XMLDBIndex('description');
    $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array($idx_field));
    if (!index_exists($table, $index)) {
        $result = add_index($table, $index, false, false);
    }
    return $result;
}

function post_check_9()
{
    global $dbh;
    if (!index_exists("bayes_token", "bayes_token_idx1")) {
        return array(false, "Error creating index bayes_token_idx1");
    } else {
        return array(true, "");
    }
}

 /**
  * Given one XMLDBTable and one XMLDBIndex, return the SQL statements needded to drop the index from the table
  */
 function getDropKeySQL($xmldb_table, $xmldb_key)
 {
     $results = array();
     /// Get the key name
     $dbkeyname = find_key_name($xmldb_table, $xmldb_key);
     /// Only if such type of key generation is enabled
     $dropkey = false;
     switch ($xmldb_key->getType()) {
         case XMLDB_KEY_PRIMARY:
             if ($this->primary_keys) {
                 $template = $this->drop_primary_key;
                 $dropkey = true;
             }
             break;
         case XMLDB_KEY_UNIQUE:
             if ($this->unique_keys) {
                 $template = $this->drop_unique_key;
                 $dropkey = true;
             }
             break;
         case XMLDB_KEY_FOREIGN_UNIQUE:
         case XMLDB_KEY_FOREIGN:
             if ($this->foreign_keys) {
                 $template = $this->drop_foreign_key;
                 $dropkey = true;
             }
             break;
     }
     /// If we have decided to drop the key, let's do it
     if ($dropkey) {
         /// Replace TABLENAME, CONSTRAINTTYPE and KEYNAME as needed
         $dropsql = str_replace('TABLENAME', $this->getTableName($xmldb_table), $template);
         $dropsql = str_replace('KEYNAME', $dbkeyname, $dropsql);
         $results[] = $dropsql;
     }
     /// If we aren't dropping the keys OR if the key is XMLDB_KEY_FOREIGN (not underlying index generated
     /// automatically by the RDBMS) drop the underlying (created by us) index (if exists)
     if (!$dropkey || $xmldb_key->getType() == XMLDB_KEY_FOREIGN) {
         /// Only if they exist
         $xmldb_index = new XMLDBIndex('anyname');
         $xmldb_index->setAttributes(XMLDB_INDEX_UNIQUE, $xmldb_key->getFields());
         if (index_exists($xmldb_table, $xmldb_index)) {
             $results = array_merge($results, $this->getDropIndexSQL($xmldb_table, $xmldb_index));
         }
     }
     /// If the key is XMLDB_KEY_FOREIGN_UNIQUE, drop the UNIQUE too
     if ($xmldb_key->getType() == XMLDB_KEY_FOREIGN_UNIQUE && $this->unique_keys) {
         ///Duplicate the key
         $xmldb_key->setType(XMLDB_KEY_UNIQUE);
         $results = array_merge($results, $this->getDropKeySQL($xmldb_table, $xmldb_key));
     }
     /// Return results
     return $results;
 }

function xmldb_block_email_list_upgrade($oldversion = 0)
{
    global $CFG, $THEME, $DB;
    $result = true;
    // If is set upgrade_blocks_savepoint function
    $existfunction = false;
    if (!function_exists('upgrade_blocks_savepoint')) {
        $existfunction = true;
    }
    /// And upgrade begins here. For each one, you'll need one
    /// block of code similar to the next one. Please, delete
    /// this comment lines once this file start handling proper
    /// upgrade code.
    if ($result && $oldversion < 2007062205) {
        $fields = array('mod/email:viewmail', 'mod/email:addmail', 'mod/email:reply', 'mod/email:replyall', 'mod/email:forward', 'mod/email:addsubfolder', 'mod/email:updatesubfolder', 'mod/email:removesubfolder');
        /// Remove no more used fields
        $table = new XMLDBTable('capabilities');
        foreach ($fields as $name) {
            $field = new XMLDBField($name);
            $result = $result && drop_field($table, $field);
        }
        // Active cron block of email_list
        if ($result) {
            if ($email_list = get_record('block', 'name', 'email_list')) {
                $email_list->cron = 1;
                update_record('block', $email_list);
            }
        }
        if ($existfunction) {
            /// Block savepoint reached
            upgrade_blocks_savepoint($result, 2007062205, 'email_list');
        }
    }
    // force
    $result = true;
    if ($result && $oldversion < 2007072003) {
        // Add marriedfolder2courses flag on email_preferences
        $table = new XMLDBTable('email_preference');
        $field = new XMLDBField('marriedfolders2courses');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', null);
        $result = $result && add_field($table, $field);
        // Add course ID on email_folder
        $table = new XMLDBTable('email_folder');
        $field = new XMLDBField('course');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', null);
        $result = $result && add_field($table, $field);
        // Add index
        $key = new XMLDBKey('course');
        $key->setAttributes(XMLDB_KEY_FOREIGN, array('course'), 'course', array('id'));
        $result = $result && add_key($table, $key);
        if ($existfunction) {
            /// Block savepoint reached
            upgrade_blocks_savepoint($result, 2007072003, 'email_list');
        }
    }
    if ($result && $oldversion < 2008061400) {
        // Add reply and forwarded info field on email_mail.
        $table = new XMLDBTable('email_send');
        $field = new XMLDBField('answered');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '4', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', null);
        $result = $result && add_field($table, $field);
        if ($existfunction) {
            /// Block savepoint reached
            upgrade_blocks_savepoint($result, 2008061400, 'email_list');
        }
    }
    // Solve old problems
    if ($result && $oldversion < 2008061600) {
        $table = new XMLDBTable('email_preference');
        $field = new XMLDBField('marriedfolders2courses');
        if (!field_exists($table, $field)) {
            $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', null);
            $result = $result && add_field($table, $field);
        }
        $table = new XMLDBTable('email_folder');
        $field = new XMLDBField('course');
        if (!field_exists($table, $field)) {
            $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', null);
            $result = $result && add_field($table, $field);
            // Add index
            $key = new XMLDBKey('course');
            $key->setAttributes(XMLDB_KEY_FOREIGN, array('course'), 'course', array('id'));
            $result = $result && add_key($table, $key);
        }
        if ($existfunction) {
            /// Block savepoint reached
            upgrade_blocks_savepoint($result, 2008061600, 'email_list');
        }
    }
    // Add new index
    if ($result and $oldversion < 2008081602) {
        // Add combine key on foldermail
        $table = new XMLDBTable('email_foldermail');
        $index = new XMLDBIndex('folderid-mailid');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('folderid', 'mailid'));
        if (!index_exists($table, $index)) {
            /// Launch add index
            $result = $result && add_index($table, $index);
        }
        if ($existfunction) {
//.........这里部分代码省略.........

//.........这里部分代码省略.........
        while ($rec = rs_fetch_next_record($rs)) {
            $magicnumber = ouwiki_generate_magic_number();
            set_field('ouwiki_subwikis', 'magic', $magicnumber, 'id', $rec->id);
        }
        rs_close($rs);
        /// Changing nullability of field magic on table ouwiki_subwikis to not null
        $field->setAttributes(XMLDB_TYPE_INTEGER, '16', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, null, 'userid');
        /// Launch change of nullability for field magic
        $result = $result && change_field_notnull($table, $field);
    }
    if ($result && $oldversion < 2008073000) {
        /// Define field completionpages to be added to ouwiki
        $table = new XMLDBTable('ouwiki');
        $field = new XMLDBField('completionpages');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '9', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'editend');
        /// Launch add field completionpages
        $result = $result && add_field($table, $field);
        /// Define field completionedits to be added to ouwiki
        $field = new XMLDBField('completionedits');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '9', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'completionpages');
        /// Launch add field completionedits
        $result = $result && add_field($table, $field);
    }
    if ($result && $oldversion < 2008100600) {
        /// Define field deletedat to be added to ouwiki_versions
        $table = new XMLDBTable('ouwiki_versions');
        $field = new XMLDBField('deletedat');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, null, null, null, null, null, 'changeprevsize');
        /// Launch add field deletedat (provided field does not already exist)
        if (!field_exists($table, $field)) {
            $result = $result && add_field($table, $field);
        }
    }
    if ($result && $oldversion < 2010022300) {
        // Add ouwiki delete page capability to admin role if it exists
        // Check whether necessary
        $name = 'Administrator';
        $shortname = 'admin';
        if (($role = get_record('role', 'name', $name)) || ($role = get_record('role', 'shortname', $shortname))) {
            if ($sitecontext = get_context_instance(CONTEXT_SYSTEM, SITEID)) {
                // Check role has delete page capability (assign if not)
                $cap = 'mod/ouwiki:deletepage';
                if (!($rcap = get_record('role_capabilities', 'roleid', $role->id, 'capability', $cap, 'contextid', $sitecontext->id))) {
                    assign_capability($cap, CAP_ALLOW, $role->id, $sitecontext->id);
                }
            }
        }
    }
    if ($result && $oldversion < 2009120801) {
        $tw = new transaction_wrapper();
        /// Define table ouwiki_annotations to be created
        $table = new XMLDBTable('ouwiki_annotations');
        /// Adding fields to table ouwiki_annotations
        $table->addFieldInfo('id', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, XMLDB_SEQUENCE, null, null, null);
        $table->addFieldInfo('pageid', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, null);
        $table->addFieldInfo('userid', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, null, null, null, null, null);
        $table->addFieldInfo('timemodified', XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, null);
        $table->addFieldInfo('content', XMLDB_TYPE_TEXT, 'medium', null, XMLDB_NOTNULL, null, null, null, null);
        /// Adding keys to table ouwiki_annotations
        $table->addKeyInfo('primary', XMLDB_KEY_PRIMARY, array('id'));
        /// Launch create table for ouwiki_annotations - if it does not already exist (extra precaution)
        if (!table_exists($table)) {
            $result = $result && create_table($table);
        }
        /// Define field locked to be added to ouwiki_pages
        $table = new XMLDBTable('ouwiki_pages');
        $field = new XMLDBField('locked');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '1', null, XMLDB_NOTNULL, null, null, null, '0', 'currentversionid');
        /// Launch add field locked - if it does not already exist (extra precaution)
        if (!field_exists($table, $field)) {
            $result = $result && add_field($table, $field);
        }
        if ($result) {
            $tw->commit();
        } else {
            $tw->rollback();
        }
    }
    if ($result && $oldversion < 2010022300) {
        /// Define field commenting to be added to ouwiki
        $table = new XMLDBTable('ouwiki');
        $field = new XMLDBField('commenting');
        $field->setAttributes(XMLDB_TYPE_CHAR, '20', null, null, null, null, null, 'default', 'completionedits');
        /// Launch add field commenting - if it does not already exist (extra precaution)
        if (!field_exists($table, $field)) {
            $result = $result && add_field($table, $field);
        }
    }
    if ($result && $oldversion < 2010042201) {
        /// Define key subwikiid (foreign) to be added to ouwiki_pages
        $table = new XMLDBTable('ouwiki_pages');
        $key = new XMLDBKey('subwikiid');
        $key->setAttributes(XMLDB_KEY_FOREIGN, array('subwikiid'), 'ouwiki_subwikis', array('id'));
        /// Launch add key subwikiid
        if (!index_exists($table, $key)) {
            $result = $result && add_key($table, $key);
        }
    }
    return $result;
}

//.........这里部分代码省略.........
        $cron->callfunction = 'export_cleanup_old_exports';
        $cron->minute = '0';
        $cron->hour = '3,13';
        $cron->day = '*';
        $cron->month = '*';
        $cron->dayofweek = '*';
        insert_record('cron', $cron);
    }
    if ($oldversion < 2009070600) {
        // This was forgotten as part of the 1.0 -> 1.1 upgrade
        if ($data = check_upgrades('blocktype.file/html')) {
            upgrade_plugin($data);
        }
    }
    if ($oldversion < 2009070700) {
        foreach (array('addfriend', 'removefriend', 'addfriendrequest', 'removefriendrequest') as $eventtype) {
            $event = (object) array('name' => $eventtype);
            ensure_record_exists('event_type', $event, $event);
        }
    }
    if ($oldversion < 2009070900) {
        if (is_mysql()) {
            execute_sql("ALTER TABLE {usr} DROP FOREIGN KEY {usr_las_fk}");
            execute_sql("ALTER TABLE {usr} DROP INDEX {usr_las_ix}");
        }
        $table = new XMLDBTable('usr');
        $field = new XMLDBField('lastauthinstance');
        drop_field($table, $field);
    }
    if ($oldversion < 2009080600) {
        $table = new XMLDBTable('view');
        $index = new XMLDBIndex('view_own_type_uix');
        $index->setAttributes(XMLDB_INDEX_UNIQUE, array('owner'));
        if (!index_exists($table, $index)) {
            // Delete duplicate profile views if there are any, then add an index
            // that will prevent it happening again - but only on postgres, as it's
            // the only db that supports partial indexes
            if ($viewdata = get_records_sql_array("\n                SELECT owner, id\n                FROM {view}\n                WHERE owner IN (\n                    SELECT owner\n                    FROM {view}\n                    WHERE type = 'profile'\n                    GROUP BY owner\n                    HAVING COUNT(*) > 1\n                )\n                AND type = 'profile'\n                ORDER BY owner, id", array())) {
                require_once 'view.php';
                $seen = array();
                foreach ($viewdata as $record) {
                    $seen[$record->owner][] = $record->id;
                }
                foreach ($seen as $owner => $views) {
                    // Remove the first one, which is their real profile view
                    array_shift($views);
                    foreach ($views as $viewid) {
                        delete_records('artefact_feedback', 'view', $viewid);
                        delete_records('view_feedback', 'view', $viewid);
                        delete_records('view_access', 'view', $viewid);
                        delete_records('view_access_group', 'view', $viewid);
                        delete_records('view_access_usr', 'view', $viewid);
                        delete_records('view_access_token', 'view', $viewid);
                        delete_records('view_autocreate_grouptype', 'view', $viewid);
                        delete_records('view_tag', 'view', $viewid);
                        delete_records('usr_watchlist_view', 'view', $viewid);
                        if ($blockinstanceids = get_column('block_instance', 'id', 'view', $viewid)) {
                            foreach ($blockinstanceids as $id) {
                                if (table_exists('blocktype_wall_post')) {
                                    delete_records('blocktype_wall_post', 'instance', $id);
                                }
                                delete_records('view_artefact', 'block', $id);
                                delete_records('block_instance', 'id', $id);
                            }
                        }
                        delete_records('view', 'id', $viewid);

//.........这里部分代码省略.........
        /// Normalize course->shortname MDL-10026
        /// Changing precision of field shortname on table course to (100)
        $table = new XMLDBTable('course');
        $field = new XMLDBField('shortname');
        $field->setAttributes(XMLDB_TYPE_CHAR, '100', null, XMLDB_NOTNULL, null, null, null, null, 'fullname');
        /// Launch change of precision for field shortname
        $result = $result && change_field_precision($table, $field);
        upgrade_main_savepoint($result, 2007080800);
    }
    if ($result && $oldversion < 2007080900) {
        /// Add context.path & index
        $table = new XMLDBTable('context');
        $field = new XMLDBField('path');
        $field->setAttributes(XMLDB_TYPE_CHAR, '255', null, null, null, null, null, null, 'instanceid');
        $result = $result && add_field($table, $field);
        $table = new XMLDBTable('context');
        $index = new XMLDBIndex('path');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('path'));
        $result = $result && add_index($table, $index);
        /// Add context.depth
        $table = new XMLDBTable('context');
        $field = new XMLDBField('depth');
        $field->setAttributes(XMLDB_TYPE_INTEGER, '2', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'path');
        $result = $result && add_field($table, $field);
        /// make sure the system context has proper data
        get_system_context(false);
        upgrade_main_savepoint($result, 2007080900);
    }
    if ($result && $oldversion < 2007080903) {
        /// Define index
        $table = new XMLDBTable('grade_grades');
        $index = new XMLDBIndex('locked-locktime');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('locked', 'locktime'));
        if (!index_exists($table, $index)) {
            /// Launch add index
            $result = $result && add_index($table, $index);
        }
        /// Define index
        $table = new XMLDBTable('grade_items');
        $index = new XMLDBIndex('locked-locktime');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('locked', 'locktime'));
        if (!index_exists($table, $index)) {
            /// Launch add index
            $result = $result && add_index($table, $index);
        }
        /// Define index itemtype-needsupdate (not unique) to be added to grade_items
        $table = new XMLDBTable('grade_items');
        $index = new XMLDBIndex('itemtype-needsupdate');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('itemtype', 'needsupdate'));
        if (!index_exists($table, $index)) {
            /// Launch add index itemtype-needsupdate
            $result = $result && add_index($table, $index);
        }
        /// Define index
        $table = new XMLDBTable('grade_items');
        $index = new XMLDBIndex('gradetype');
        $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('gradetype'));
        if (!index_exists($table, $index)) {
            /// Launch add index
            $result = $result && add_index($table, $index);
        }
        upgrade_main_savepoint($result, 2007080903);
    }
    if ($result && $oldversion < 2007081000) {
        require_once $CFG->dirroot . '/question/upgrade.php';
        $result = $result && question_upgrade_context_etc();