I believe this is a matter of personal preference, and you might get different opinions from different people...
I'd say - if you already own both QlikView and Qlik Sense licenses, and your team is equally good with both tools, I'd keep my ETL processes in QlikView and develop the visual layer in the tool of your choice per application. My reasons for that are:
- While the script language is nearly identical in both tools, QlikView allows a bit more advanced functionality - for example, existing wizards for loading and transforming "dirty" spreadsheets, etc...
- QlikView Publisher is a lot more versatile than Qlik Sense tasks - you can use triggers, pass variables, and use many other advanced features that were not implemented in Qlik Sense.
On the other hand, Qlik keeps developing and enhancing the visual data loading functionality in Qlik Sense. If you'd like to leverage these new "drag-and-drop" data loading capabilities, you might prefer to implement a similar ETL structure in Qlik Sense.
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