Type IV
The Type 4 method is usually referred to as using "history tables", where one table keeps the current data, and an additional table is used to keep a record of some or all changes.
For the above example the original table name is Supplier and the history table is Supplier_History.
| Supplier_key | Supplier_Code | Supplier_Name | Supplier_State |
|---|---|---|---|
| 123 | ABC | Acme Supply Co | IL |
| Supplier_key | Supplier_Code | Supplier_Name | Supplier_State | Create_Date |
|---|---|---|---|---|
| 123 | ABC | Acme Supply Co | CA | 22-Dec-2004 |
This method resembles how database audit tables and change data capture techniques function.
Read more about this topic: Slowly Changing Dimension
Famous quotes containing the word type:
“They had supposed their formula was fixed.
They had obeyed instructions to devise
A type of cold, a type of hooded gaze.
But when the Negroes came they were perplexed.
These Negroes looked like men....”
—Gwendolyn Brooks (b. 1917)