Load Data into MotherDuck

Use this skill when the job is getting data into MotherDuck correctly and efficiently, not just writing one ad hoc import query.

Source Of Truth

• Prefer current MotherDuck loading, cloud-storage, and Postgres-endpoint loading docs first.
• Use CREATE SECRET and cloud-storage docs for protected-object-store workflows.
• Use the DuckDB database upload docs when the source is an existing local .duckdb, .ddb, or attached DuckDB database.
• Keep the loading advice aligned with MotherDuck's documented posture:
  • batch over streaming
  • Parquet over CSV when you control the format
  • dataframe, COPY, CTAS, or INSERT ... SELECT over row-by-row inserts
  • native MotherDuck storage first unless DuckLake is explicitly required

Default Posture

• Start by classifying the source: object storage or HTTPS, local file or local DuckDB, in-memory rows, or an external database.
• Prefer CREATE TABLE AS SELECT for first loads and INSERT INTO ... SELECT for appends.