This field is only available if automatic partition handling is chosen. In order to know when to create a new partition QAD Data Warehouse Designer executes a query against the fact table and the date dimension to acquire each unique period. When dealing with a large fact table, such a query may take a long time to complete. This field can be used to include the components of the 'Where' clause to restrict the amount of data examined. For example we may enter 'dss_update_time < GETDATE()-14' to only look at fact table records that have been inserted or updated in the last 14 days. This should still allow us to catch any new partitions and add them. The first time a cube is converted to auto partitioning handling, a full pass of the fact table should occur to allow inclusion of every partition. This field should therefore only be populated once the cube has been initially built with all partitions intact.