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Database / DuckDB Interview questions

What is the difference between MotherDuck's hybrid execution and running DuckDB fully locally?

Running DuckDB fully locally means every table, file, and computation involved in a query lives and executes entirely on the local machine, with no external service involved at all. MotherDuck's hybrid execution model instead lets a single query span both a local DuckDB instance and MotherDuck's cloud backend, automatically routing each part of the query to wherever the relevant data actually lives.

Fully local DuckDBMotherDuck hybrid execution
All data and computation stay on the local machine.Query can span local files and cloud-hosted tables in one statement.
No dependency on any external service.Depends on a MotherDuck connection for the cloud-hosted portion.
Limited by local machine's storage and compute.Cloud-hosted tables can scale beyond local machine constraints.

This matters practically for a workflow like joining a small local reference file against a much larger table that lives in MotherDuck's cloud storage: rather than needing to either download the entire cloud table locally first or upload the local file to the cloud before querying, hybrid execution lets that join happen directly across both locations within a single query, with MotherDuck's engine deciding how to split and coordinate the actual execution.

MotherDuck's hybrid execution allows a single query to:
A practical benefit of hybrid execution is:

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