CREATE SECRET

MotherDuck enables you to store your cloud storage credentials for convenience, using the familiar DuckDB CREATE SECRET syntax. See DuckDB CREATE SECRET documentation.

Make sure to add either PERSISTENT or IN MOTHERDUCK keyword to create MotherDuck secrets. Secrets stored in MotherDuck are fully encrypted.

note

You can use the PERSISTENT keyword to create a local file persistent secret in DuckDB as well. It gets stored unencrypted in the ~/.duckdb/stored_secrets directory.

When you've loaded the MotherDuck extension, PERSISTENT secrets are stored encrypted in MotherDuck. Locally persisted secrets are not impacted.

You can still create locally persisted secrets when using MotherDuck by specifying the secret storage backend: CREATE SECRET IN LOCAL_FILE.

When using MotherDuck, the statement below creates a cloud-persistent secret stored in MotherDuck.

Syntax

CREATE [OR REPLACE] PERSISTENT SECRET [secret_name] (
    TYPE <S3, GCS, R2, AZURE, HUGGINGFACE>, 
    <storage-specific properties>
);

CREATE [OR REPLACE] SECRET [secret_name] IN MOTHERDUCK (
    TYPE <S3, GCS, R2, AZURE, HUGGINGFACE>, 
    <storage-specific properties>
);

Secret Paramters

Below is a complete list of the supported parameters for S3, GCS, and R2 secrets:

Name	Description	Secret	Type	Default
ENDPOINT	Specify a custom S3 endpoint	S3, GCS, R2	STRING	s3.amazonaws.com for S3,
KEY_ID	The ID of the key to use	S3, GCS, R2	STRING	-
REGION	The region for which to authenticate (should match the region of the bucket to query)	S3, GCS, R2	STRING	us-east-1
SECRET	The secret of the key to use	S3, GCS, R2	STRING	-
SESSION_TOKEN	Optionally, a session token can be passed to use temporary credentials	S3, GCS, R2	STRING	-
URL_COMPATIBILITY_MODE	Can help when URLs contain problematic characters	S3, GCS, R2	BOOLEAN	true
URL_STYLE	Either vhost or path	S3, GCS, R2	STRING	vhost for S3, path for R2 and GCS
USE_SSL	Whether to use HTTPS or HTTP	S3, GCS, R2	BOOLEAN	true
ACCOUNT_ID	The R2 account ID to use for generating the endpoint URL	R2	STRING	-
KMS_KEY_ID	AWS KMS (Key Management Service) key for Server Side Encryption S3	S3	STRING	-
SCOPE	Scope of secret resolution; In the case of multiple matching secrets, the longest prefix is chosen	S3, GCS, R2	STRING	-

info

Because of SSL certificate verification requirements, S3 bucket names that contain dots (.) cannot be accessed using vhost style URLs. This is due to AWS's SSL wildcard certificate (*.s3.amazonaws.com) which only validates single-level subdomains. To resolve this SSL Issue: use URL_STYLE path in your secret.

Example Usage

To manually create a S3 secret in MotherDuck:

CREATE SECRET IN MOTHERDUCK (
    TYPE S3,
    KEY_ID 's3_access_key',
    SECRET 's3_secret_key',
    REGION 'us-east-1',
    SCOPE 'my-bucket-path'
);

This creates a new secret with a default name (i.e. __default_s3) and a default scope (i.e. [s3://, s3n://, s3a://]) used for path matching explained below.

info

DuckDB uses the SCOPE parameter to determine which secret to use. When using persistent secrets or public buckets, scoping the secrets is important so that the databases use the correct secret. Imprecise scoping will lead to authentication errors.

You can learn more in the DuckDB documentation.

Secret Providers

MotherDuck supports the same secret providers as DuckDB.

To create a secret by automatically fetching credentials using mechanisms provided by the AWS SDK, see AWS CREDENTIAL_CHAIN provider.

To create a secret by automatically fetching credentials using mechanisms provided by the Azure SDK, see Azure CREDENTIAL_CHAIN provider.

To create a secret by automatically fetching credentials using mechanisms provided by the Hugging Face CLI, see Hugging Face CREDENTIAL_CHAIN provider.

To store a secret from a given secret provider in MotherDuck, simply specify PERSISTENT or IN MOTHERDUCK keyword in addition.

Example Usage

To store a secret configured through aws configure:

CREATE PERSISTENT SECRET aws_secret (
      TYPE S3,
      PROVIDER CREDENTIAL_CHAIN
  );

To store a secret configured through az configure:

CREATE SECRET azure_secret IN MOTHERDUCK (
      TYPE AZURE,
      PROVIDER CREDENTIAL_CHAIN,
      ACCOUNT_NAME 'some-account'
  );

Querying with Secrets

Secret scope is supported in the same way as in DuckDB to allow multiple secrets of the same type to be stored in MotherDuck. When there are multiple local (i.e. in memory and store in local file) and remote (i.e. MotherDuck) secrets of the same type, scope matching (secret scope against the file path) happens to determine which secret to use to open a file. Both local and remote secrets are considered in scope matching.

In the case of multiple matching secrets, the secret with the longest matching scope prefix is chosen.

In the case of multiple secrets stored in different secret storages sharing the same scope (e.g. the default scope if not specified), matching secret is chosen based on the following order: local temp secret > local_file secret > MotherDuck secret.

To see which secret (either local or remote) is being used by MotherDuck, the DuckDB which_secret table function can be used, which takes a path and the secret type.

Example Usage

To see which secret is used to open a file:

FROM which_secret('s3://my-bucket/my_dataset.parquet', 's3');
┌───────────────────────┬────────────┬────────────┐
│         name          │ persistent │  storage   │
│        varchar        │  varchar   │  varchar   │
├───────────────────────┼────────────┼────────────┤
│ __default_s3          │ PERSISTENT │ motherduck │
└───────────────────────┴────────────┴────────────┘