Basic Doubts in SAP HANA Calculation View

[Former Member]

Hi All,

I'm learning SAP HANA on my own and i have some basic questions and would appreciate your help..

1)What is the use of "Output as Aggregated Column" in aggreation node in Calc View --- My understanding is if we use raw tables directly and want to aggregrate the results before hitting the final default aggreation node that's whn the aggreation node comes in picture and also if i'm just using analytical views in calc views i don't see any benefit of aggegration nodes as the output of Analytical Views are already aggrgated

2)Whats the difference in using aggregration node and just selecting fields as output (Not Output as Aggregated column ) vs using Projection node and selecting fields as output ?

3) There are no Restricted Measures in Calc Views right ?

4)When we call the Analytical views from Calc Views do we need to call the Analytical View from _sys_bic or drag directly from the package ?

I have gone through tons of materials ..I would appreciate if you could explain with a simple example rather than pointing towards some documents

Thanks in Advance

Satyam

[Former Member]

1) This just forces that measure to aggregate as you tell it to. If you have a top level aggregation node then you don't need a second one in most cases. One example where you do is where you want to use exception aggregation and use the keep flag. This permits very powerful analytics for specific circumstances like weighted averages or year on year.

2) If you use a projection node then it won't aggregate, it's that simple. So you will get all results, without aggregation or grouping.

3) Correct. In most cases I use an Analytic View as a base, and a Calculation View to handle anything that the Analytic View can't do, like year on year, and some types of exception aggregation where the aggregation happens at multiple levels. Calc View should be a last resort. If you need RKF in a Calc View, you can probably model the requirement using a Scripted Calc View.

4) I usually press the + button next to the projection node and search for it. Remember to always use a projection node when you consume an Analytic View in a Calculation View.