Unit 6: Use Case #3 – Many-to-One Mapping

The example use case has Dimensions SEX, EDU_LEVEL, and STAT_UNIT, whose values are to be combined in a mapped DSD as a single Dimension with ID INDICATOR and unique series INDICATOR1, INDICATOR2, INDICATOR3.

This type of use case can be solved by creating three component maps:

• Component Map 1: Source=SEX Target=INDICATOR
• Component Map 2: Source=EDU_LEVEL Target=INDICATOR
• Component Map 3: Source=STAT_UNIT Target=INDICATOR

Each component map is backed by a representation map, which maps the value of the Unique Key to the output as follows:

Select the representation map to enlarge.

The second solution involves creating a single component map, which maps the three sources (SEX, EDU_LEVEL, STAT_UNIT) to the output INDICATOR.

A Single Representation Map is required to map the three inputs to the INDICATOR output.

• Representation Map = SEX:EDU_LEVEL:STAT_UNIT -> INDICATOR
• Values:
  • _T:PRIMARY:ENROLMENT=INDICATOR1
  • F:PRIMARY:ENROLMENT=INDICATOR2
  • M:PRIMARY:ENROLMENT=INDICATOR3

As with the one-to-many use case, the choice of whether to split the mapping up into separate components (Solution A) versus a single rule (Solution B), should be based on what will be more maintainable and understandable, along with whether individual mapping rules will be reused by other structure maps or not.