Creating filters
The first question that comes to our mind is why do we need filters? As discussed in Chapter 2, SAP HANA Data Modeling Approach, Modeling Principles section—consideration to make in Chapter 1, Kickoff – Before We Start: The idea is to filter the data at the lowest layer and only bring the data that is actually required by the query. (Quoting it from Chapter 1, Kickoff – Before We Start).That is, we should try to reduce data transfer between the engines. This can be achieved using the following steps:
Creating client dependent views: The data is automatically filtered to one client.
Using domain fix values: This can be used for several fields.
Creating filters: This is defined during design time.
Creating and using the
WHEREclauses in queries: This is defined at the runtime of the SQL query.
Using the preceding steps not only ensures that we minimize data transfer between the engines, but also helps to reduce the larger result sets between the HANA database and the client/application...
