diff --git a/src/main/java/org/gcube/portlets/user/td/expressionwidget/server/ExpressionServiceImpl.java b/src/main/java/org/gcube/portlets/user/td/expressionwidget/server/ExpressionServiceImpl.java
index 391af51..f771b80 100644
--- a/src/main/java/org/gcube/portlets/user/td/expressionwidget/server/ExpressionServiceImpl.java
+++ b/src/main/java/org/gcube/portlets/user/td/expressionwidget/server/ExpressionServiceImpl.java
@@ -59,6 +59,7 @@ public class ExpressionServiceImpl extends RemoteServiceServlet implements
 		
 		C_ExpressionParser parser=new C_ExpressionParser();
 		Expression exp=parser.parse(columnFilterSession.getCexpression());
+		logger.debug("Service Expression:"+exp);
 		
 		map.put(Constants.PARAMETER_EXPRESSION, exp);