If you have attended QlikView training courses and done some work with QlikView modeling, there are a few things that you will know about, but I will review them just to be sure that we are all on the same page.
QlikView uses an associative model to connect data rather than a join model. A join model is the traditional approach to data queries. In the join model, you craft a SQL query across multiple tables in the database, telling the database management system (DBMS) how those tables should be joined—whether left, inner, outer, and so on. The DBMS might have a system in place to optimize the performance of those queries. Each query tends to be run in isolation, returning a result set that can be either further explored—Excel pivot tables are a common use case here—or used to build a final report. Queries might have parameters to enable different reports to be executed, but each execution is still in isolation. In fact, it is the approach that...