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More from Claudia Gomez (17)
Dw design 3_surro_keys
- 4. A surrogate key is a unique identifier for data
warehouse records that replaces source primary keys
(business/natural keys)
4
- 5. Protect against changes in source systems
5
- 6. Allow integration from multiple sources
6
- 7. Enable rows that do not exist in source data
7
- 8. Track changes over time (e.g. new customer instances
when addresses change)
8
- 9. Replace text keys with integers for efficiency
9
- 10. Higher performance with numeric keys than with
long, alphanumeric keys
10
- 11. The Data Warehouse Toolkit.Second
Edition.The Complete Guide to Dimensional
Modeling.Ralph Kimball.Margy Ross