diff --git a/src/test/java/org/gcube/documentstore/persistence/PersistenceBackendFactoryTest.java b/src/test/java/org/gcube/documentstore/persistence/PersistenceBackendFactoryTest.java
index 631d502..ef2d3ca 100644
--- a/src/test/java/org/gcube/documentstore/persistence/PersistenceBackendFactoryTest.java
+++ b/src/test/java/org/gcube/documentstore/persistence/PersistenceBackendFactoryTest.java
@@ -19,7 +19,10 @@ public class PersistenceBackendFactoryTest {
 	
 	@Test
 	public void parsingTest() throws Exception {
-		PersistenceBackendFactory.getPersistenceBackend(null);
+		PersistenceBackend persistenceBackend = PersistenceBackendFactory.getPersistenceBackend(null);
+		logger.debug("{}", persistenceBackend);
 		PersistenceBackendFactory.flushAll(100, TimeUnit.MILLISECONDS);
+		PersistenceBackendFactory.flush(null, 100, TimeUnit.MILLISECONDS);
+		persistenceBackend.flush(100, TimeUnit.MILLISECONDS);
 	}
 }