SAP HANA Engine:
SAP HANA has mainly 3 types of engines that are used based on the views required by the model.
Join Engine:
- Used when querying an Attribute View
- The join engine is also used, when you run plain SQL.
OLAP Engine:
- Used for Analytic view (without calculated columns).
Calculation Engine:
- Used for Analytic views with calculated attributes and Calculation views
Note: To check what engine is used to process a query: simply run the Plan Visualization on your query.
Q1: What If I execute a standard ANSI92 SQL statement from a BI tool or in SAP HANA Studio. What engines will be used?
Ans: Depends on what objects you reference in your query. If you're just querying plain base tables then the join engine will be used. As soon as you reference an analytic or calculation view, the other engines will be employed as well.
Q2: If my Analytic View foundation is joined to attribute views, is both the OLAP and JOIN Engine used?
Ans: Nope - during activation of the analytic views, the joins in the attribute views get 'flattened' and included in the analytic view run time object. Only the OLAP engine will be used then.
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