Motherduck Load Data

---
name: motherduck-load-data
description: Load and ingest data into MotherDuck from local files, object storage (S3, GCS, Azure, R2), HTTPS, dataframes, or external databases. Use for any import or bulk-load task — CSV, Parquet, JSON, Delta, Iceberg, local DuckDB database upload — and for choosing between CTAS, INSERT...SELECT, COPY, cloud-storage secrets, and Postgres-endpoint versus native DuckDB-client paths.
license: MIT
---

# 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.