UD Fields in Fulfillment Workbench

Does anyone know where the UD fields that are in the Fulfillment Workbench grids come from? I would like to use them but have no idea where they are originating from since the fields are in a custom DataView that Epicor did.

Our UD fields which are on OrderRel table show up on Fulfilment workbench. Try that table first.

Second choice is to use a SQL query:

SELECT      c.name  AS 'ColumnName'
            ,t.name AS 'TableName'
FROM        sys.columns c
JOIN        sys.tables  t   ON c.object_id = t.object_id
WHERE       c.name LIKE '%UDShortChar01 %'
ORDER BY    TableName

Thanks, I’ll start there.