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CREATE DATABASE SCOPED CREDENTIAL (Transact-SQL)

  • Άρθρο

Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Analytics Platform System (PDW) SQL database in Microsoft Fabric

Creates a database credential. A database credential is not mapped to a server login or database user. The credential is used by the database to access to the external location anytime the database is performing an operation that requires access.

Transact-SQL syntax conventions

Syntax

CREATE DATABASE SCOPED CREDENTIAL credential_name
WITH IDENTITY = 'identity_name'
    [ , SECRET = 'secret' ]
[ ; ]

Arguments

credential_name

Specifies the name of the database scoped credential being created. credential_name can't start with the number (#) sign. System credentials start with ##. The maximum length of credential_name is 128 characters.

IDENTITY = 'identity_name'

Specifies the name of the account to be used when connecting outside the server.

  • To import a file from Azure Blob Storage or Azure Data Lake Storage using a shared key, the identity name must be SHARED ACCESS SIGNATURE. For more information about shared access signatures, see Using Shared Access Signatures (SAS). Only use IDENTITY = SHARED ACCESS SIGNATURE for a shared access signature.
  • To import a file from Azure Blob Storage using a managed identity, the identity name must be MANAGED IDENTITY.
  • When using Kerberos (Windows Active Directory or MIT KDC) do not use the domain name in the IDENTITY argument. It should just be the account name.
  • In a SQL Server instance, if creating a database scoped credential with a Storage Access Key used as the SECRET, IDENTITY is ignored.
  • WITH IDENTITY is not required if the container in Azure Blob storage is enabled for anonymous access. For an example querying Azure Blob storage, see Importing into a table from a file stored on Azure Blob storage.

Important

The only PolyBase external data source that supports Kerberos authentication is Hadoop. All other external data sources (SQL Server, Oracle, Teradata, MongoDB, generic ODBC) only support Basic Authentication.

  • To load data into Azure Synapse Analytics, any valid value can be used for IDENTITY.
  • In an Azure Synapse Analytics serverless SQL pool, database scoped credentials can specify a workspace managed identity, service principal name, or shared access signature (SAS) token. Access via a user identity, enabled by Microsoft Entra pass-through authentication, is also possible with a database scoped credential, as is anonymous access to publicly available storage. For more information, see Supported storage authorization types.
  • In an Azure Synapse Analytics dedicated SQL pool, database scoped credentials can specify shared access signature (SAS) token, custom application identity, workspace managed identity, or storage access key.

SECRET = 'secret'

Specifies the secret required for outgoing authentication. SECRET is required to import a file from Azure Blob storage. To load from Azure Blob storage into Azure Synapse Analytics or Parallel Data Warehouse, the Secret must be the Azure Storage Key.

Warning

The SAS key value might begin with a '?' (question mark). When you use the SAS key, you must remove the leading '?'. Otherwise your efforts might be blocked.

Remarks

A database scoped credential is a record that contains the authentication information that is required to connect to a resource outside SQL Server. Most credentials include a Windows user and password.

To protect the sensitive information inside the database scoped credential, a database master key (DMK) is required. The DMK is a symmetric key that encrypts the secret in the database scoped credential. The database must have a DMK before any database scoped credentials can be created. A DMK should be encrypted with a strong password. Azure SQL Database will create a DMK with a strong, randomly selected password as part of creating the database scoped credential, or as part of creating a server audit. Users can't create the DMK on a logical master database. The master key password is unknown to Microsoft and not discoverable after creation. For this reason, creating a DMK before creating a database scoped credential is recommended. For more information, see CREATE MASTER KEY (Transact-SQL).

When IDENTITY is a Windows user, the secret can be the password. The secret is encrypted using the service master key (SMK). If the SMK is regenerated, the secret is re-encrypted using the new SMK.

When granting permissions for a shared access signatures (SAS) for use with a PolyBase external table, select both Container and Object as allowed resource types. If not granted, you may receive error 16535 or 16561 when attempting to access the external table.

Information about database scoped credentials is visible in the sys.database_scoped_credentials catalog view.

Here are some applications of database scoped credentials:

Permissions

Requires CONTROL permission on the database.

SQL Server 2022

Starting in SQL Server 2022 (16.x) a new type of connector was introduced, using REST-API calls replacing HADOOP. For Azure Blob Storage and Azure Data Lake Gen 2 the only supported authentication method is SHARED ACCESS SIGNATURE.

For more information, see CREATE EXTERNAL DATA SOURCE.

Examples

A. Creating a database scoped credential for your application

The following example creates the database scoped credential called AppCred. The database scoped credential contains the Windows user Mary5 and a password.

-- Create a db master key if one does not already exist, using your own password.
CREATE MASTER KEY ENCRYPTION BY PASSWORD='<EnterStrongPasswordHere>';

-- Create a database scoped credential.
CREATE DATABASE SCOPED CREDENTIAL AppCred WITH IDENTITY = 'Mary5',
    SECRET = '<EnterStrongPasswordHere>';

B. Creating a database scoped credential for a shared access signature

The following example creates a database scoped credential that can be used to create an external data source, which can do bulk operations, such as BULK INSERT and OPENROWSET.

-- Create a db master key if one does not already exist, using your own password.
CREATE MASTER KEY ENCRYPTION BY PASSWORD='<EnterStrongPasswordHere>';

-- Create a database scoped credential.
CREATE DATABASE SCOPED CREDENTIAL MyCredentials
WITH IDENTITY = 'SHARED ACCESS SIGNATURE',
SECRET = 'QLYMgmSXMklt%2FI1U6DcVrQixnlU5Sgbtk1qDRakUBGs%3D';

C. Creating a database scoped credential for PolyBase Connectivity to Azure Data Lake Store

The following example creates a database scoped credential that can be used to create an external data source, which can be used by PolyBase in Azure Synapse Analytics.

Azure Data Lake Store uses a Microsoft Entra application for service to service authentication.

Create a Microsoft Entra application and document your client_id, OAuth_2.0_Token_EndPoint, and Key before you try to create a database scoped credential.

-- Create a db master key if one does not already exist, using your own password.
CREATE MASTER KEY ENCRYPTION BY PASSWORD='<EnterStrongPasswordHere>';

-- Create a database scoped credential.
CREATE DATABASE SCOPED CREDENTIAL ADL_User
WITH
    IDENTITY = '<client_id>@<OAuth_2.0_Token_EndPoint>',
    SECRET = '<key>'
;

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