Documents for QlikView related information.
I have worked on a qlikview design model where I have three different layers as mentioned before in all the QlikView solutions.
I have listed out the benefits as I can think. I appreciate if anyone add more to it.
QVD Layer(Extract Layer):
Data Model Layer:
My thoughts :
The QVD Layer (which I tend to call the Extract layer) should be exactly the same as the data source. No transformation. The reason being is that you can track back your sums through each layer. You would match your Extract with your data source. Match the Model with the Extract, etc. That way you can easily see where a data issue may occurring.
The next layer I would have as a transform (Model). The difference in my mind is the Model is ready for a binary load to the UI / Dashboard where as a transform would create a new set of QVD's with all the calcs / renames / joins / mapping / etc.
Benefit of the transform over a model is that multiple dashboards can mix and match and re-use the same QVD's (this is also the same as the extract layer, no point going to the same data source twice)
Sorry for all the posts. For some reason I was being blocked when trying to submit the whole thing....
I agree with both your points. Having Extraction layer without transformation is good and Transformation layer where you can create additional field(s) which include and not limited to calculation, derive new fields and many more is good idea.
Data trace-ability is possible and easy with this approach.
Thank you all.
I have added your points to the list.
Good attempt. However there are some drawbacks of this approach. Now a days there is a bit fight happening between ETL and ELT approaches..
Good One.. However, I also agree with Jd Sreeni's point
Thanks for the Inputs sreeni.
Can you please provide more details so that I can add those to the above mentioned topic.