diff --git a/src/main/java/org/gcube/portlets/user/td/gwtservice/server/TDGWTServiceImpl.java b/src/main/java/org/gcube/portlets/user/td/gwtservice/server/TDGWTServiceImpl.java
index 6b8be67..98513ba 100644
--- a/src/main/java/org/gcube/portlets/user/td/gwtservice/server/TDGWTServiceImpl.java
+++ b/src/main/java/org/gcube/portlets/user/td/gwtservice/server/TDGWTServiceImpl.java
@@ -3880,10 +3880,10 @@ public class TDGWTServiceImpl extends RemoteServiceServlet implements
 			OpExecutionDirector director = new OpExecutionDirector();
 			director.setOperationExecutionBuilder(opEx);
 			director.constructOperationExecution();
-			ArrayList<OperationExecution> invocations = director
-					.getListOperationExecution();
+			OperationExecution invocation = director
+					.getOperationExecution();
 
-			if (invocations == null) {
+			if (invocation == null) {
 				throw new TDGWTServiceException(
 						"Error in invocation: Operation not supported");
 			}
@@ -3891,8 +3891,8 @@ public class TDGWTServiceImpl extends RemoteServiceServlet implements
 					.getId());
 
 			TabularResourceId serviceTR = new TabularResourceId(id);
-			logger.debug("OperationInvocation: \n" + invocations.toString());
-			Task trTask = service.executeBatch(invocations, serviceTR);
+			logger.debug("OperationInvocation: \n" + invocation.toString());
+			Task trTask = service.execute(invocation, serviceTR);
 			logger.debug("Filter Column on service: TaskId " + trTask.getId());
 
 			TaskWrapper taskWrapper = new TaskWrapper(trTask,