diff --git a/src/main/java/li/strolch/persistence/postgresql/PostgreSqlOrderDao.java b/src/main/java/li/strolch/persistence/postgresql/PostgreSqlOrderDao.java
index af99372bd..245c91da3 100644
--- a/src/main/java/li/strolch/persistence/postgresql/PostgreSqlOrderDao.java
+++ b/src/main/java/li/strolch/persistence/postgresql/PostgreSqlOrderDao.java
@@ -31,6 +31,7 @@ import javax.xml.parsers.SAXParserFactory;
 import javax.xml.transform.sax.SAXResult;
 
 import li.strolch.model.Order;
+import li.strolch.model.OrderVisitor;
 import li.strolch.model.Tags;
 import li.strolch.model.query.OrderQuery;
 import li.strolch.model.xml.OrderToSaxVisitor;
@@ -155,7 +156,7 @@ public class PostgreSqlOrderDao extends PostgresqlDao<Order> implements OrderDao
 	}
 
 	@Override
-	public List<Order> doQuery(OrderQuery query) {
+	public <U> List<U> doQuery(OrderQuery query, OrderVisitor<U> orderVisitor) {
 		// TODO Auto-generated method stub
 		return null;
 	}
diff --git a/src/main/java/li/strolch/persistence/postgresql/PostgreSqlResourceDao.java b/src/main/java/li/strolch/persistence/postgresql/PostgreSqlResourceDao.java
index 4f24d24a7..d0455a956 100644
--- a/src/main/java/li/strolch/persistence/postgresql/PostgreSqlResourceDao.java
+++ b/src/main/java/li/strolch/persistence/postgresql/PostgreSqlResourceDao.java
@@ -29,6 +29,7 @@ import javax.xml.parsers.SAXParserFactory;
 import javax.xml.transform.sax.SAXResult;
 
 import li.strolch.model.Resource;
+import li.strolch.model.ResourceVisitor;
 import li.strolch.model.Tags;
 import li.strolch.model.query.ResourceQuery;
 import li.strolch.model.xml.ResourceToSaxVisitor;
@@ -144,7 +145,7 @@ public class PostgreSqlResourceDao extends PostgresqlDao<Resource> implements Re
 	}
 
 	@Override
-	public List<Resource> doQuery(ResourceQuery query) {
+	public <U> List<U> doQuery(ResourceQuery query, ResourceVisitor<U> resourceVisitor) {
 		// TODO Auto-generated method stub
 		return null;
 	}