Add an uid_lower column to the oc_users table

Add a new column.
In the postSchemaChange copy over the values (with lower).

This should work just fine as this is a very simple operation.
Even if you have 1M users in the db backend this should be fast
enough.

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

core/Migrations/Version14000Date20180404140050.php

@@ -0,0 +1,78 @@
+<?php
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2018 Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program 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 Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC\Core\Migrations;
+
+use OCP\DB\ISchemaWrapper;
+use OCP\IDBConnection;
+use OCP\Migration\SimpleMigrationStep;
+use OCP\Migration\IOutput;
+
+/**
+ * Auto-generated migration step: Please modify to your needs!
+ */
+class Version14000Date20180404140050 extends SimpleMigrationStep {
+
+	/** @var IDBConnection */
+	private $connection;
+
+	public function __construct(IDBConnection $connection) {
+		$this->connection = $connection;
+	}
+
+	/**
+	 * @param IOutput $output
+	 * @param \Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 */
+	public function changeSchema(IOutput $output, \Closure $schemaClosure, array $options) {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		$table = $schema->getTable('users');
+
+		$table->addColumn('uid_lower', 'string', [
+			'notnull' => false,
+			'length' => 64,
+			'default' => '',
+		]);
+		$table->addIndex(['uid_lower'], 'user_uid_lower');
+
+		return $schema;
+	}
+
+	/**
+	 * @param IOutput $output
+	 * @param \Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 */
+	public function postSchemaChange(IOutput $output, \Closure $schemaClosure, array $options) {
+		$qb = $this->connection->getQueryBuilder();
+
+		$qb->update('users')
+			->set('uid_lower', $qb->createFunction('LOWER(`uid`)'));
+		$qb->execute();
+	}
+}

version.php

@@ -29,7 +29,7 @@
 // between betas, final and RCs. This is _not_ the public version number. Reset minor/patchlevel
 // when updating major/minor version number.
 
-$OC_Version = array(14, 0, 0, 1);
+$OC_Version = array(14, 0, 0, 2);
 
 // The human readable string
 $OC_VersionString = '14.0.0 alpha';