In the case of a time dimension, if the key is the date in numeric format, the method to get the surrogate key is simply changing the metadata for the date, in the same way we did when loading the dimension: from date to string first, and then from string to number.
If, instead of the date you have a regular surrogate key, you can use a Database lookup step to get the surrogate key.
The following table summarizes the different possibilities to get surrogate keys:
|
Dimension type |
Method to get the surrogate key |
Sample dimension |
|
Type I SCD |
Database lookup step. |
REGIONS |
|
Type II SCD |
Dimension L/U step. |
PUZZLES |
|
Junk and Mini |
Combination L/U step if you load the dimension ... |
