Hi...to know which which flowfile completed, you can use a putemail processor to get an email when a particular flowfiles is finished. You can make it dynamic using db.table.name attribute which is added by generatetablefetch...if you have a lot of flowfiles for a single table, you can merge the flowfiles using mergecontent on tablename to give you periodic or batch completion status.
Another way could be to write success and failures to for e.g hive table and you can check the table for completions and failure.
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