Developer Documentation Library > Data Model > Extending the UNICOM Intelligence Data Model > Creating a CDSC > CDSCs and variables
 
CDSCs and variables
The Provider handles all variables, including system variables, in the same way; it does not give a special meaning to any particular type of variables.
A CDSC should not implement its own variables. However, it can use the MDM system variables internally for special purposes. For example, a read/write CDSC can assume that the serial variable will always exist and can use it as part of a primary key.
See also
Structure of the CDSC interface
How should a CDSC return categorical data?
Creating a CDSC