A unique feature of the MDIS is that it does not import records directly from import files. Rather, it transforms the original import file records into virtual extended records. Then this transformed virtual extended record is imported into the MDM repository.
The transformation process can be broken down into three phases:
Structural Transformation Stage: Convert source tables into a single virtual table using import map rules.
Value Transformation Stage: Source values on the virtual table are converted according to the rules of the import map.
Import Stage: Transformed virtual extended records are imported into the MDM repository.
These phases are shown in the illustration as follows:
Let us look at each of these three phases in detail.