Dss_source_system
This pseudo dimension is designed to identify a data source for a dimension row. Its purpose is to handle non conformed dimensions, or changes in source systems. If its use is not desired (default) then leave this field blank.
For example:
An organization has a number of factories. These factories are referenced by all of the operational systems. The production system has its own code for each factory and this is the unique means of identifying the factory. The distribution system has a factory short name which it uses for the unique identifier. The raw materials system simply uses the factory name. It is probably not practical or even desirable to force these source systems to utilize a standard factory identification method, so instead we allow the dimension to be non conformed. We do however, insist on a standard factory name convention, so that our reports and queries will join information when the factory name is used.
In such an example the dss_source_system_key is used to identify the source of the data for the dimension row. It also adds to the unique business key, so that two source systems can utilize the same code to refer to different entities. This key also provides a degree of future proofing in the data warehouse, to assist in the possible changing of an underlying source system.
The generated procedure code will always set the key value of this table to 1. So, manual code changes will be required to make use of the functionality that this table offers.
When dimensions are built the dss_source_system_key is added by default. It can be deleted if the need for such a feature is not seen.
If this table is to be given a different name then it and all its columns can be renamed or the following steps can be taken:
1 Create a new table by dragging the column dss_source_system_name from dss_source_system into a dimension target.
2 Change the object type from dimension view to dimension and specify the new table name. (see note above on the use of "dss_").
3 Rename the dss_source_system_name column to match the new table name.
4 Delete the last two columns.
5 Under the tables properties, change the table type to 'Mapping table'. This will prevent the table from being seen as a dimension in the documentation.
6 Change the dss_source_system table name in the screen above, via the tools/ancillary column defaults menu option.