Is Autoloader suitable to load full dumps?

[quakenbush]

Hi,

I recently completed the fundamentals & advanced data engineer exam, yet I've got a question about Autoloader. Please don't go too hard on me, since I lack practical experience at this point in time 😉

Docs say this is incremental ingestion, so it's easy to load new files that contain all-new records that go into the stream. There's also the option to allow overwriting of files. What if the files provided by a source system are

A) full dumps which contain ALL records currently present in the system (missing records were deleted) so the loader needs to check for new, changed or missing records

B) delta, only new or changed records (deletes must be flagged)

Is Autoloader/COPY INTO still a good fit? Perhaps using a MERGE logic?

Thanks

Roger

[Kaniz · Accepted solution]

Hi @quakenbush, Congratulations on completing the data engineer exams! 🎉 .

Autoloader is designed for incremental ingestion, efficiently loading new files with fresh records into the stream. 

However, let’s analyze how it fits in the scenarios you’ve described:

Full Dumps (Option A):

• In this case, the provided files contain all records currently present in the system, including any deletions. The loader needs to identify new, changed, or missing records.
• Autoloader can still be a good fit here. You can use a MERGE logic to handle the following:
  • Inserts: New records from the full dump.
  • Updates: Changed records (if any).
  • Deletes: Identify missing records (not present in the full dump) and flag them for deletion.
• The MERGE operation allows you to synchronize the data stream with the full dump efficiently.

Delta Files (Option B):

• With delta files, you only receive new or changed records. Deletions are flagged.
• Autoloader is well-suited for this scenario. You can directly ingest the delta files into the stream.
• Use a MERGE logic to handle the following:
  • Inserts: New records from the delta files.
  • Updates: Changed records.
  • Deletes: Process the flagged deletions.
• Autoloader’s incremental approach aligns perfectly with this use case.

In summary, Autoloader/COPY INTO remains a good fit for both scenarios. Leveraging a MERGE operation allows you to efficiently manage the data stream, whether dealing with full dumps or delta files. 

Keep up the great work, and practical experience will reinforce your understanding! 😊🚀

[Kaniz]

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