Master Data Analysis
When you analyze two data sources in the Match transformation, you must identify a source as the master data set. The transformation compares data values from each record in the data set that you specify with the corresponding values in every record in the second data set.
In many organizations, a master data set constitutes a permanent, high-quality data store. Before you add records to a master data set, use the Match transformation to verify that the records do not add duplicate information to the master data.
Master Data Example
A bank maintains a master data set of customer account records. The bank updates the master data set every day with records that identify new customer accounts. The bank uses a duplicate analysis mapping to verify that the new records do not duplicate the customer information in the master data set. The master data set and the new account tables have a common structure, and the tables use the same type of database. Therefore, the bank can reuse the duplicate analysis mapping each time it needs to update the master data set.
Directionality in Master Data Set Analysis
The Match transformation compares records from one data set to another in a single direction. The transformation compares each record in the master data set to all of the records in the second data set. The transformation does not compare each record in the second data set to all of the records in the master data set. Therefore, the selection of the master data set can affect the results of the match analysis.
The following table shows two data sets that you can compare in identity match analysis:
Data Set 1 | Data Set 2 |
|---|
Alex Bell | Alexander Bell |
Alexander Graham Bell | Thomas Edison |
Alva Edison | Nicola Tesla |
Marie Curie | Irene Joliot Curie |
Dorothy Crowfoot | Dorothy Hodgkin |
If you select Data Set 1 as the master data set and you select the Best Match output option, the output includes the following records:
- •Alex Bell, Alexander Bell
- •Alexander Graham Bell, Alexander Bell
If you select Data Set 2as the master data set and you select the Best Match output option, the output includes the following records:
- •Alexander Bell, Alex Bell
When Data Set 2 is the master data set, the transformation cannot match Alexander Bell and Alexander Graham Bell, because Alexander Bell already matches Alex Bell in the output data.
Mapping Reuse
If you add data to a master data set on a regular basis, configure a duplicate analysis mapping that you can reuse. You can reuse the mapping if the port configurations on the data source that you compare to the master data set do not change.
When you run the mapping, verify that the transformation specifies the master data and the newer data. You can run the mapping without any other configuration update.