diff --git a/lib/GroupBackend.php b/lib/GroupBackend.php
index 11f915139..9ffe220ef 100644
--- a/lib/GroupBackend.php
+++ b/lib/GroupBackend.php
@@ -61,7 +61,7 @@ public function inGroup($uid, $gid): bool {
 			->where($qb->expr()->eq('uid', $qb->createNamedParameter($uid)))
 			->andWhere($qb->expr()->eq('gid', $qb->createNamedParameter($gid)))
 			->setMaxResults(1)
-			->execute();
+			->executeQuery();
 
 		$result = count($stmt->fetchAll()) > 0;
 		$stmt->closeCursor();
@@ -76,7 +76,7 @@ public function getUserGroups($uid): array {
 		$cursor = $qb->select('gid')
 			->from(self::TABLE_MEMBERS)
 			->where($qb->expr()->eq('uid', $qb->createNamedParameter($uid)))
-			->execute();
+			->executeQuery();
 
 		$groups = [];
 		while ($row = $cursor->fetch()) {
@@ -105,7 +105,7 @@ public function getGroups($search = '', $limit = null, $offset = null): array {
 
 		$query->setMaxResults($limit)
 			->setFirstResult($offset);
-		$result = $query->execute();
+		$result = $query->executeQuery();
 
 		$groups = [];
 		while ($row = $result->fetch()) {
@@ -129,7 +129,7 @@ public function groupExists($gid): bool {
 		$cursor = $qb->select('gid')
 			->from(self::TABLE_GROUPS)
 			->where($qb->expr()->eq('gid', $qb->createNamedParameter($gid)))
-			->execute();
+			->executeQuery();
 		$result = $cursor->fetch();
 		$cursor->closeCursor();
 
@@ -182,7 +182,7 @@ public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0): arra
 			$query->setFirstResult($offset);
 		}
 
-		$result = $query->execute();
+		$result = $query->executeQuery();
 
 		$users = [];
 		while ($row = $result->fetch()) {
@@ -203,7 +203,7 @@ public function createGroup(string $gid, string $samlGid = null): bool {
 				->setValue('gid', $builder->createNamedParameter($gid))
 				->setValue('displayname', $builder->createNamedParameter($displayName))
 				->setValue('saml_gid', $builder->createNamedParameter($samlGid))
-				->execute();
+				->executeStatement();
 		} catch (UniqueConstraintViolationException $e) {
 			$result = 0;
 		}
@@ -220,7 +220,7 @@ public function addToGroup(string $uid, string $gid): bool {
 			$qb->insert(self::TABLE_MEMBERS)
 				->setValue('uid', $qb->createNamedParameter($uid))
 				->setValue('gid', $qb->createNamedParameter($gid))
-				->execute();
+				->executeStatement();
 			return true;
 		} catch (\Exception $e) {
 			throw new AddUserToGroupException($e->getMessage());