You can specify a data slice when you create a partition using the Partition wizard. When you select dimension slices in the Partition wizard, the wizard attempts to create a filter on the fact table to specify the data to be included in the partition. This generated filter is combined with any filter you specify on the source data for the partition. However, the generated filter can be created only if the level’s MemberKeyColumn and MemberNameColumn properties point to the same column. This is the default situation established when a dimension level is created, but the property values can differ if the dimension or cube has been edited.
It is suggested that you create an explicit filter to specify only the data from the fact table that is to be included in the partition, whether or not the MemberKeyColumn and MemberNameColumn property values are the same. An explicit filter is not necessary if the source data table for the partition contains only data that is to be included in the partition. However, an explicit filter ensures that only the intended data is included in the partition, and assists in accurately merging partitions when fact tables are combined.