Writen by
Devil
2:06 AM
-
0
Comments
SCD type 2 stores the entire history the data in the dimension table. With type 2 we can store unlimited history in the dimension table. In type 2, you can store the data in three different ways. They are
- Versioning
- Flagging
- Effective Date
SCD Type 2 Versioning: In versioning method, a sequence number is used to represent the change. The latest sequence number always represents the current row and the previous sequence numbers represents the past data.
Example a customer (Deb) moves from Cuttack to Bangalore and the version number will be incremented. The dimension table will look as below
SCD Type 2 Flagging: In flagging method, a flag column is created in the dimension table. The current record will have the flag value as 1 and the previous records will have the flag as 0.
SCD Type 2 Effective Date: In Effective Date method, the period of the change is tracked using the start_date and end_date columns in the dimension table.
No comments
Post a Comment