Thanks for your question.
......If you are thinking of older legacy BI tools, or SQL-based query tools that NEED to create metadata layers (semantic layers) in order to work with the BI tool -- and then pass either native / ansi SQL or translated API calls to the back-end data source....then NO - Qlik does not work that way. We do not maintain a semantic layer. Data is loaded from the source into the in-memory data model, compressed, indexed and becomes part of the app (Qlik Sense or QlikView). The client UI then aggregates on the fly and updates the visualizations at the speed of thought without going back to the source. (we have solutions for direct query access too if needed).
Let us know what else you would like to know.
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