Aggregating data
While QlikView shines in dealing with massive data volumes, sometimes we just do not need to load everything at an atomic level. Data aggregation can, for example, be used in deployments where document segmentation by detail is needed, in which case two documents are created to serve different user groups and analysis needs: one document will have all data with the highest level of detail and another one will have a similar data model but with aggregated (reduced) tables. This way, users are better served by keeping a balance between performance and analysis needs.
In this section, we will implement a document segmentation scenario by aggregating the Flight Data table to create a second document intended for executive users, who only require summary data.
Aggregating the Flight Data table
When aggregating data, the first step is always to define which dimension fields will be left out and which ones will be kept in the summarized table. We should analyze this question by looking...