Connection Parameters

Introduced or updated: v1.2.294

Connection parameters are key-value pairs used to establish secure links to external storage services like Amazon S3. These parameters are crucial for tasks such as creating stages, copying data into Databend, and querying external files.

For specific connection details per storage service, see the tables below.

Amazon S3

The following table lists connection parameters for accessing an Amazon S3-like storage service:

Parameter	Required?	Description
endpoint_url	Yes	Endpoint URL for Amazon S3-like storage service.
access_key_id	Yes	Access key ID for identifying the requester.
secret_access_key	Yes	Secret access key for authentication.
enable_virtual_host_style	No	Whether to use virtual host-style URLs. Defaults to false.
master_key	No	Optional master key for advanced data encryption.
region	No	AWS region where the bucket is located.
security_token	No	Security token for temporary credentials.

note

• If the endpoint_url parameter is not specified in the command, Databend will create the stage on Amazon S3 by default. Therefore, when you create an external stage on an S3-compatible object storage or other object storage solutions, be sure to include the endpoint_url parameter.

• The region parameter is not required because Databend can automatically detect the region information. You typically don't need to manually specify a value for this parameter. In case automatic detection fails, Databend will default to using 'us-east-1' as the region. When deploying Databend with MinIO and not configuring the region information, it will automatically default to using 'us-east-1', and this will work correctly. However, if you receive error messages such as "region is missing" or "The bucket you are trying to access requires a specific endpoint. Please direct all future requests to this particular endpoint", you need to determine your region name and explicitly assign it to the region parameter.

Examples

CREATE STAGE my_s3_stage
  's3://my-bucket'
  CONNECTION = (
    ACCESS_KEY_ID = '<your-ak>',
    SECRET_ACCESS_KEY = '<your-sk>'
  );
  
CREATE STAGE my_minio_stage
  's3://databend'
  CONNECTION = (
    ENDPOINT_URL = 'http://localhost:9000',
    ACCESS_KEY_ID = 'ROOTUSER',
    SECRET_ACCESS_KEY = 'CHANGEME123'
  );

To access your Amazon S3 buckets, you can also specify an AWS IAM role and external ID for authentication. By specifying an AWS IAM role and external ID, you can provide more granular control over which S3 buckets a user can access. This means that if the IAM role has been granted permissions to access only specific S3 buckets, then the user will only be able to access those buckets. An external ID can further enhance security by providing an additional layer of verification. For more information, see https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-role.html

The following table lists connection parameters for accessing Amazon S3 storage service using AWS IAM role authentication:

Parameter	Required?	Description
endpoint_url	No	Endpoint URL for Amazon S3.
role_arn	Yes	ARN of the AWS IAM role for authorization to S3.
external_id	No	External ID for enhanced security in role assumption.

Examples

CREATE STAGE my_s3_stage
  's3://my-bucket'
  CONNECTION = (
    ROLE_ARN = 'arn:aws:iam::123456789012:role/my-role',
    EXTERNAL_ID = 'my-external-id'
  );

Azure Blob

The following table lists connection parameters for accessing Azure Blob Storage:

Parameter	Required?	Description
endpoint_url	Yes	Endpoint URL for Azure Blob Storage.
account_key	Yes	Azure Blob Storage account key for authentication.
account_name	Yes	Azure Blob Storage account name for identification.

Examples

CREATE STAGE my_azure_stage
  'azblob://my-container'
  CONNECTION = (
    ACCOUNT_NAME = 'myaccount',
    ACCOUNT_KEY = 'myaccountkey',
    ENDPOINT_URL = 'https://<your-storage-account-name>.blob.core.windows.net'
  );

Google GCS

The following table lists connection parameters for accessing Google Cloud Storage:

Parameter	Required?	Description
credential	Yes	Google Cloud Storage credential for authentication.

To get the credential, you could follow the topic Create a service account key from the Google documentation to create and download a service account key file. After downloading the service account key file, you could convert it into a base64 string via the following command:

base64 -i -o ~/Desktop/base64-encoded-key.txt

Examples

CREATE STAGE my_gcs_stage
  'gcs://my-bucket'
  CONNECTION = (
    CREDENTIAL = '<your-base64-encoded-credential>'
  );

Alibaba Cloud OSS

The following table lists connection parameters for accessing Alibaba Cloud OSS:

Parameter	Required?	Description
access_key_id	Yes	Alibaba Cloud OSS access key ID for authentication.
access_key_secret	Yes	Alibaba Cloud OSS access key secret for authentication.
endpoint_url	Yes	Endpoint URL for Alibaba Cloud OSS.
presign_endpoint_url	No	Endpoint URL for presigning Alibaba Cloud OSS URLs.

Examples

CREATE STAGE my_oss_stage
  'oss://my-bucket'
  CONNECTION = (
    ACCESS_KEY_ID = '<your-ak>',
    ACCESS_KEY_SECRET = '<your-sk>',
    ENDPOINT_URL = 'https://<bucket-name>.<region-id>[-internal].aliyuncs.com'
  );

Tencent COS

The following table lists connection parameters for accessing Tencent Cloud Object Storage (COS):

Parameter	Required?	Description
endpoint_url	Yes	Endpoint URL for Tencent Cloud Object Storage.
secret_id	Yes	Tencent Cloud Object Storage secret ID for authentication.
secret_key	Yes	Tencent Cloud Object Storage secret key for authentication.

Examples

CREATE STAGE my_cos_stage
  'cos://my-bucket'
  CONNECTION = (
    SECRET_ID = '<your-secret-id>',
    SECRET_KEY = '<your-secret-key>',
    ENDPOINT_URL = '<your-endpoint-url>'
  );

HDFS

The following table lists connection parameters for accessing Hadoop Distributed File System (HDFS):

Parameter	Required?	Description
name_node	Yes	HDFS NameNode address for connecting to the cluster.

Examples

CREATE STAGE my_hdfs_stage
  'hdfs://my-bucket'
  CONNECTION = (
    NAME_NODE = 'hdfs://<namenode-host>:<port>'
  );

WebHDFS

The following table lists connection parameters for accessing WebHDFS:

Parameter	Required?	Description
endpoint_url	Yes	Endpoint URL for WebHDFS.
delegation	No	Delegation token for accessing WebHDFS.

Examples

CREATE STAGE my_webhdfs_stage
  'webhdfs://my-bucket'
  CONNECTION = (
    ENDPOINT_URL = 'http://<namenode-host>:<port>'
  );

HuggingFace

The following table lists connection parameters for accessing Hugging Face:

Parameter	Required?	Description
repo_type	No (default: dataset)	The type of the Hugging Face repository. Can be dataset or model.
revision	No (default: main)	The revision for the Hugging Face URI. Could be a branch, tag, or commit of the repository.
token	No	The API token from Hugging Face, which may be required for accessing private repositories or certain resources.

Examples

CREATE STAGE my_huggingface_stage
  'hf://opendal/huggingface-testdata/'
  CONNECTION = (
    REPO_TYPE = 'dataset'
    REVISION = 'main'
  );