Basically, we should be able to edit the final output (data destination) columns directly in the Dataflow Gen2, without needing to go to the Warehouse itself to add the new columns (using T-SQL).
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For Replace mode: use similar logic as Spark .mode("overwrite").option("overwriteSchema", "true").
For Append mode: use similar logic as Spark .mode("append").option("mergeSchema", "true")
