Hello jane,
Azure Data Explorer is great for ingesting timeseries data and processing in inside the database using table update policies.
Unfortunately, Azure Data Explorer does not generate events based on changed data.
You need to use a polling strategy to check for new rows to occur.
Azure Stream Analytics is in fact a good choice to distribute data to different endpoints/resources.
I'm not sure what you mean with lack of flexibility.
Having the ability to join streams and reference data, a n extensive query language, easily extensible with javascript or even machine learning is far from beging not flexible.
The fact you can put the logic under version control via Visual Studio Code or even test the query real time, is a blizz.
Just give it some time if you are new to Azure Stream Analytics.
There are alternatives though.
Check out Azure Functions (custom code), Logic apps (a no-code experience) or Azure Data Factory as alternatives to Azure Stream Analytics.
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