A user has 10 files in a stage containing new customer data. The ingest operation completes with no errors using the following command:

COPY INTO my_table FROM @my_stage;

The next day, the user adds 10 more files to the stage, which now contains a mixture of new customer data and updates to the previous data. The user did not remove the 10 original files.

If the user runs the same COPY INTO command again, what will happen?