@Wenjian Feng Welcome to the Microsoft Q&A platform.
With ADF you can schedule a query to run and get new data, but you'll need to do it to each table you have. A smart idea would be changing the application to insert in Oracle and also in a queue that would trigger your ETL.
Note: It is a good choice to use ADF if you have limited changes/updates. In case, if you have more changes/updates - we need to do it to each table you have. That's becomes too complicated.
You may refer SO thread which addressing similar issue: Near real-time ETL of Oracle data to Azure SQL
Hope this helps. Do let us know if you any further queries.
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