diff --git a/lib/private/Files/Cache/HomeCache.php b/lib/private/Files/Cache/HomeCache.php
index b86a31fe4d..e66ed7d972 100644
--- a/lib/private/Files/Cache/HomeCache.php
+++ b/lib/private/Files/Cache/HomeCache.php
@@ -52,12 +52,19 @@ class HomeCache extends Cache {
 		}
 		if ($entry && $entry['mimetype'] === 'httpd/unix-directory') {
 			$id = $entry['fileid'];
-			$sql = 'SELECT SUM(`size`) AS f1 ' .
-			   'FROM `*PREFIX*filecache` ' .
-				'WHERE `parent` = ? AND `storage` = ? AND `size` >= 0';
-			$result = \OC_DB::executeAudited($sql, [$id, $this->getNumericStorageId()]);
-			if ($row = $result->fetchRow()) {
-				$result->closeCursor();
+
+			$query = $this->connection->getQueryBuilder();
+			$query->selectAlias($query->func()->sum('size'), 'f1')
+				->from('filecache')
+				->where($query->expr()->eq('parent', $query->createNamedParameter($id)))
+				->andWhere($query->expr()->eq('storage', $query->createNamedParameter($this->getNumericStorageId())))
+				->andWhere($query->expr()->gte('size', $query->createNamedParameter(0)));
+
+			$result = $query->execute();
+			$row = $result->fetch();
+			$result->closeCursor();
+
+			if ($row) {
 				list($sum) = array_values($row);
 				$totalSize = 0 + $sum;
 				$entry['size'] += 0;
diff --git a/lib/private/Files/Cache/Storage.php b/lib/private/Files/Cache/Storage.php
index 62228e1629..b11cd5799d 100644
--- a/lib/private/Files/Cache/Storage.php
+++ b/lib/private/Files/Cache/Storage.php
@@ -126,9 +126,14 @@ class Storage {
 	 * @return string|null either the storage id string or null if the numeric id is not known
 	 */
 	public static function getStorageId($numericId) {
-		$sql = 'SELECT `id` FROM `*PREFIX*storages` WHERE `numeric_id` = ?';
-		$result = \OC_DB::executeAudited($sql, [$numericId]);
-		if ($row = $result->fetchRow()) {
+		$query = \OC::$server->getDatabaseConnection()->getQueryBuilder();
+		$query->select('id')
+			->from('storages')
+			->where($query->expr()->eq('numeric_id', $query->createNamedParameter($numericId)));
+		$result = $query->execute();
+		$row = $result->fetch();
+		$result->closeCursor();
+		if ($row) {
 			return $row['id'];
 		} else {
 			return null;
@@ -170,9 +175,14 @@ class Storage {
 	 * @param int $delay amount of seconds to delay reconsidering that storage further
 	 */
 	public function setAvailability($isAvailable, int $delay = 0) {
-		$sql = 'UPDATE `*PREFIX*storages` SET `available` = ?, `last_checked` = ? WHERE `id` = ?';
 		$available = $isAvailable ? 1 : 0;
-		\OC_DB::executeAudited($sql, [$available, time() + $delay, $this->storageId]);
+
+		$query = \OC::$server->getDatabaseConnection()->getQueryBuilder();
+		$query->update('storages')
+			->set('available', $query->createNamedParameter($available))
+			->set('last_checked', $query->createNamedParameter(time() + $delay))
+			->where($query->expr()->eq('id', $query->createNamedParameter($this->storageId)));
+		$query->execute();
 	}
 
 	/**
@@ -193,12 +203,17 @@ class Storage {
 	public static function remove($storageId) {
 		$storageId = self::adjustStorageId($storageId);
 		$numericId = self::getNumericStorageId($storageId);
-		$sql = 'DELETE FROM `*PREFIX*storages` WHERE `id` = ?';
-		\OC_DB::executeAudited($sql, [$storageId]);
+
+		$query = \OC::$server->getDatabaseConnection()->getQueryBuilder();
+		$query->delete('storages')
+			->where($query->expr()->eq('id', $query->createNamedParameter($storageId)));
+		$query->execute();
 
 		if (!is_null($numericId)) {
-			$sql = 'DELETE FROM `*PREFIX*filecache` WHERE `storage` = ?';
-			\OC_DB::executeAudited($sql, [$numericId]);
+			$query = \OC::$server->getDatabaseConnection()->getQueryBuilder();
+			$query->delete('filecache')
+				->where($query->expr()->eq('storage', $query->createNamedParameter($numericId)));
+			$query->execute();
 		}
 	}
 }
diff --git a/tests/lib/Files/Cache/ScannerTest.php b/tests/lib/Files/Cache/ScannerTest.php
index f9c05d52ee..29e619cd09 100644
--- a/tests/lib/Files/Cache/ScannerTest.php
+++ b/tests/lib/Files/Cache/ScannerTest.php
@@ -206,19 +206,19 @@ class ScannerTest extends \Test\TestCase {
 	public function testBackgroundScanNestedIncompleteFolders() {
 		$this->storage->mkdir('folder');
 		$this->scanner->backgroundScan();
-		
+
 		$this->storage->mkdir('folder/subfolder1');
 		$this->storage->mkdir('folder/subfolder2');
-		
+
 		$this->storage->mkdir('folder/subfolder1/subfolder3');
 		$this->cache->put('folder', ['size' => -1]);
 		$this->cache->put('folder/subfolder1', ['size' => -1]);
-		
+
 		// do a scan to get the folders into the cache.
 		$this->scanner->backgroundScan();
 
 		$this->assertTrue($this->cache->inCache('folder/subfolder1/subfolder3'));
-		
+
 		$this->storage->file_put_contents('folder/subfolder1/bar1.txt', 'foobar');
 		$this->storage->file_put_contents('folder/subfolder1/subfolder3/bar3.txt', 'foobar');
 		$this->storage->file_put_contents('folder/subfolder2/bar2.txt', 'foobar');
@@ -227,7 +227,7 @@ class ScannerTest extends \Test\TestCase {
 		$this->cache->put('folder/subfolder1', ['size' => -1]);
 		$this->cache->put('folder/subfolder2', ['size' => -1]);
 		$this->cache->put('folder/subfolder1/subfolder3', ['size' => -1]);
-		
+
 		$this->scanner->backgroundScan();
 
 		$this->assertTrue($this->cache->inCache('folder/subfolder1/bar1.txt'));
@@ -343,9 +343,11 @@ class ScannerTest extends \Test\TestCase {
 		$this->assertTrue($this->cache->inCache('folder/bar.txt'));
 		$oldFolderId = $this->cache->getId('folder');
 
-		// delete the folder without removing the childs
-		$sql = 'DELETE FROM `*PREFIX*filecache` WHERE `fileid` = ?';
-		\OC_DB::executeAudited($sql, [$oldFolderId]);
+		// delete the folder without removing the children
+		$query = \OC::$server->getDatabaseConnection()->getQueryBuilder();
+		$query->delete('filecache')
+			->where($query->expr()->eq('fileid', $query->createNamedParameter($oldFolderId)));
+		$query->execute();
 
 		$cachedData = $this->cache->get('folder/bar.txt');
 		$this->assertEquals($oldFolderId, $cachedData['parent']);
@@ -367,9 +369,11 @@ class ScannerTest extends \Test\TestCase {
 		$this->assertTrue($this->cache->inCache('folder/bar.txt'));
 		$oldFolderId = $this->cache->getId('folder');
 
-		// delete the folder without removing the childs
-		$sql = 'DELETE FROM `*PREFIX*filecache` WHERE `fileid` = ?';
-		\OC_DB::executeAudited($sql, [$oldFolderId]);
+		// delete the folder without removing the children
+		$query = \OC::$server->getDatabaseConnection()->getQueryBuilder();
+		$query->delete('filecache')
+			->where($query->expr()->eq('fileid', $query->createNamedParameter($oldFolderId)));
+		$query->execute();
 
 		$cachedData = $this->cache->get('folder/bar.txt');
 		$this->assertEquals($oldFolderId, $cachedData['parent']);