When you run data domain discovery, the Data Integration Service machine processes all of the data domain rules. When you run data domain discovery on some relational sources, the Data Integration Service computes the unique values to reduce processing load due to data domain rules. This division of work is similar to the division of work when you run a column profile.

One performance consideration that differentiates data domain discovery from a column profile is the amount of processing required for columns. When you run data domain discovery, the Data Integration Service processes all the column values to find matching inference for each data domain and accurate conformance. The Profiling Service Module limits the number of data domains for each profile mapping because the complexity of each domain rule can vary. More data domains for each profile mappings can affect the processing resources of the Data Integration Service machine.

When you run data domain discovery, the Profiling Service Module analyzes the data source and profile parameters that you configured to determine the required set of mappings. The Profiling Service Module first categorizes the volume of data in the data source and then generates the required number of mappings.