1 files changed, 1 insertions, 1 deletions
diff --git a/phpBB/phpbb/db/driver/firebird.php b/phpBB/phpbb/db/driver/firebird.php
index 2df5eaf369..aef75eab15 100644
--- a/phpBB/phpbb/db/driver/firebird.php
+++ b/phpBB/phpbb/db/driver/firebird.php
@@ -398,7 +398,7 @@ class firebird extends \phpbb\db\driver\driver
 			$query_id = $this->query_result;
 		}
 
-		if ($cache && $cache->sql_exists($query_id))
+		if ($cache && !is_object($query_id) && $cache->sql_exists($query_id))
 		{
 			return $cache->sql_freeresult($query_id);
 		}