Functionally, data flows through QlikView in the following manner:1
. It starts with the source data. QlikView can load data from a large variety of sources, including ODBC, OLEDB, Flat Files (Excel, CSV, and so on), and XML. There are also many different connectors, ranging from big enterprise applications such as SAP, to social networks such as Twitter.
2. The data is loaded into QlikView using a load script. This script can be used to extract, transform, and load data into the in-memory data model or to store it to the disk in intermediary data files called QVD files.
3. Data in the in-memory database is stored in an unaggregated format, meaning all aggregations are calculated on the fly. This simplifies data modeling in QlikView, as there is no need for separate aggregation tables.
4. Selections made by the user automatically cascade throughout the entire data model and these changes are shown by QlikView's presentation engine.
5. QlikView applications can be presented in multiple clients. (Windows, Ipad, phone etc)