fix(mysql): Add migration to convert documents to lowercase

Author: jplitza

lib/Migration/Version10000Date20251228000000.php

@@ -0,0 +1,36 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2025 Jan-Philipp Litza
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\FullTextSearch_SQL\Migration;
+
+use OCP\IConfig;
+use OCP\IDBConnection;
+use OCP\DB\Types;
+use OCP\Migration\IOutput;
+use OCP\Migration\SimpleMigrationStep;
+
+class Version10000Date20251228000000 extends SimpleMigrationStep {
+	public const TABLE = 'fts_documents';
+
+	public function __construct(
+		private IDBConnection $db,
+	) {
+	}
+
+	public function postSchemaChange(IOutput $output, \Closure $schemaClosure, array $options) {
+		if ($this->db->getDatabaseProvider() != IDBConnection::PLATTFORM_MYSQL) {
+			return;
+		}
+
+		$query = $this->db->getQueryBuilder();
+		$query->update(self::TABLE)
+				->set('content', $query->func()->lower('content'));
+		$query->executeStatement();
+	}
+}