diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index a147d785cc7..8108260797c 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -908,7 +908,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 				->executeStatement();
 
 			$qbDeleteCalendarChanges = $this->db->getQueryBuilder();
-			$qbDeleteCalendarObjects->delete('calendarchanges')
+			$qbDeleteCalendarChanges->delete('calendarchanges')
 				->where($qbDeleteCalendarChanges->expr()->eq('calendarid', $qbDeleteCalendarChanges->createNamedParameter($calendarId)))
 				->andWhere($qbDeleteCalendarChanges->expr()->eq('calendartype', $qbDeleteCalendarChanges->createNamedParameter(self::CALENDAR_TYPE_CALENDAR)))
 				->executeStatement();
@@ -916,7 +916,7 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 			$this->calendarSharingBackend->deleteAllShares($calendarId);
 
 			$qbDeleteCalendar = $this->db->getQueryBuilder();
-			$qbDeleteCalendarObjects->delete('calendars')
+			$qbDeleteCalendar->delete('calendars')
 				->where($qbDeleteCalendar->expr()->eq('id', $qbDeleteCalendar->createNamedParameter($calendarId)))
 				->executeStatement();
 
diff --git a/apps/dav/lib/CardDAV/CardDavBackend.php b/apps/dav/lib/CardDAV/CardDavBackend.php
index b4fdcf922dc..041ae140f5e 100644
--- a/apps/dav/lib/CardDAV/CardDavBackend.php
+++ b/apps/dav/lib/CardDAV/CardDavBackend.php
@@ -456,11 +456,13 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 			->setParameter('addressbookid', $addressBookId, IQueryBuilder::PARAM_INT)
 			->executeStatement();
 
+		$query = $this->db->getQueryBuilder();
 		$query->delete('addressbookchanges')
 			->where($query->expr()->eq('addressbookid', $query->createParameter('addressbookid')))
 			->setParameter('addressbookid', $addressBookId, IQueryBuilder::PARAM_INT)
 			->executeStatement();
 
+		$query = $this->db->getQueryBuilder();
 		$query->delete('addressbooks')
 			->where($query->expr()->eq('id', $query->createParameter('id')))
 			->setParameter('id', $addressBookId, IQueryBuilder::PARAM_INT)
@@ -468,6 +470,7 @@ class CardDavBackend implements BackendInterface, SyncSupport {
 
 		$this->sharingBackend->deleteAllShares($addressBookId);
 
+		$query = $this->db->getQueryBuilder();
 		$query->delete($this->dbCardsPropertiesTable)
 			->where($query->expr()->eq('addressbookid', $query->createNamedParameter($addressBookId, IQueryBuilder::PARAM_INT)))
 			->executeStatement();