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As I understand that there seems to be an issue with the Azure Data Factory Sink component.
Here are some possible reasons for the issue:
Check the mapping of the surrogate key column in the sink component. Ensure that the surrogate key column is mapped correctly in the sink component.
Check the data types of the columns in the source and sink tables. Ensure that the data types of the columns in the source and sink tables are the same. If the data types are different, it can cause issues with the data flow.
Check the data flow settings. Ensure that the data flow settings are configured correctly.
while doing repro from my end I couldn't see any issue. please find the screenshots.
I hope this information helps you. Let me know if you have any further queries.