Friday, April 12, 2019

Introduction to SCD's

Lets consider the example of a company which was started many years ago. At the starting company will store all the information about the employees, products, location and so on. Later on when employees may resign, change their location, company may launch new products, their may be change in their salary over a period of time.

So their will be problem of data mismatch. In order to overcome the problem a new technique is introduced called as "Slowly Changing Dimensions".
Here the dimension tables will be updated based on their priority.

These Slowly Changing Dimensions are categorized into 3 different types based on their functions. They are 
- SCD 1
- SCD 2
- SCD 3

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