Hi Big Roux,

Thank you for your explanation and sample code.

However, I did tested with your code but I still having the same error:
[STREAMING_OUTPUT_MODE.UNSUPPORTED_OPERATION] Invalid streaming output mode: append. This output mode is not supported for streaming aggregations without watermark on streaming DataFrames/DataSets. SQLSTATE: 42KDE

I have applied the watermarking when reading the source view table.
Is there any other criteria need to apply to the f"{source}" table so that the append_flow would work?

Thank you.