A. Upload: Supports file or directory (level-one) uploading. Data can only be uploaded to a single table or table partition each time.

B. Purge: Clears the table directory. By default, use this command to clear information of the last three days.

C. Resume: If an error occurs due to the network or the Tunnel service, you can resume transmission of the file or directory after interruption.

D. Download: You can only download data to a single file. Only data in one table or partition can be downloaded to one file each time. For partitioned tables, the source partition must be specified.