Problem with Item Description Rule

Summary:

Item Description generated by rule doesn´t work properly using NVL

Content (required):

Hi!

Customer has a huge PDM with more than 3,000 item classes. I need to configurate rules to build the item description and long item description concatenating some attibutes that can be filled or null.

I´m using NVL rule but the result isn´t good. I suppose I´m configuring it wrongly.

For the item description I´m using only attributes, for example: O-RING + material + inside diameter + outside diameter + color.

if I configure:

"O-RING; " + nvl([Item].[MATERIAL].[MATERIAL_DT]; "") + nvl([Item].[DIAMETROS].[DIAM_INT_DT]; "") + nvl([Item].[DIAMETROS].[DIAM_EXT_DT]; "") + nvl([Item].[COR].[COR_DT]; "")