Hopefully, from the preceding section, you might start to see why the majority of expert QlikView developers use some kind of an ETL approach to data loading using QVDs.
There are several advantages to using an ETL approach to just load all the data directly from data sources, such as:
Speeding up overall data loading and reducing of load on database servers by archiving data to QVD
Reusing extracted data in multiple documents
Applying common business rules across multiple documents: one version of the truth
Creating conformed dimensions across multiple business processes, supporting a dimensional modeling approach
Provisioning a data layer that allows QlikView users to self-serve, without it being necessary to have database skills