Categories:

File Functions

BUILD_STAGE_FILE_URL

Generates a Snowflake-hosted file URL to a staged file using the stage name and relative file path as inputs. A file URL permits prolonged access to a specified file. That is, the file URL does not expire.

Call this SQL function in a query, user-defined function (UDF), or stored procedure.

Access files in a stage by sending the file URL in a request to the REST API for file support. When users send a file URL to the REST API to access files, Snowflake performs the following actions:

  1. Authenticate the user.

  2. Verify that the role has sufficient privileges on the stage that contains the file.

  3. Redirect the user to the staged file in the cloud storage service.

Syntax

BUILD_STAGE_FILE_URL( @<stage_name> , '<relative_file_path>' )

Arguments

stage_name

Name of the internal or external stage where the file is stored.

Note

If the stage name includes spaces or special characters, it must be enclosed in single quotes (e.g. '@"my stage"' for a stage named "my stage").

relative_file_path

Path and filename of the file relative to its location in the stage.

Usage Notes

  • The permissions required to call this SQL function differ depending on how it is called:

    SQL Operation

    Permissions Required

    Query

    USAGE (external stage) or READ (internal stage)

    Stored procedure

    The stored procedure owner (i.e. role that has the OWNERSHIP privilege on the stored procedure) must have the stage privilege: USAGE (external stage) or READ (internal stage).

    A role that queries the stored procedure only requires the USAGE privilege on the stored procedure.

    UDF

    The UDF owner (i.e. role that has the OWNERSHIP privilege on the UDF) must have the stage privilege: USAGE (external stage) or READ (internal stage).

    A role that queries the UDF only requires the USAGE privilege on the UDF.

  • An HTTP client that sends a file URL to the REST API must be configured to allow redirects.

  • When a file URL is accessed, the query history shows that the internal GET_STAGE_FILE function was called.

Output

The function returns a file URL in the following format:

https://<account_identifier>/api/files/<db_name>.<schema_name>.<stage_name>/<relative_path>

Where:

account_identifier

Hostname of the Snowflake account for your stage. The hostname starts with an account locator (provided by Snowflake) and ends with the Snowflake domain (snowflakecomputing.com):

account_locator.snowflakecomputing.com

For more details, see Account Identifiers.

Important

Currently, the function returns the account identifier in the form organization_name-account_name. When a file URL is used as input to a GET request, the API endpoint returns an error.

To resolve the error, you must manually convert the account identifier to the applicable form for your account:

account_locator.region_id or

account_locator.region_id.cloud

For more information about these forms, see Option 2: Account Locator in a Region.

In an upcoming release, the function will return file URLs in the correct form.

db_name

Name of the database that contains the stage where your files are located.

schema_name

Name of the schema that contains the stage where your files are located.

stage_name

Name of the stage where your files are located.

relative_path

Path to the files to access using the file URL.

Examples

Retrieve a file URL for a bitmap format image file in an external stage:

SELECT BUILD_STAGE_FILE_URL(@images_stage,'/us/yosemite/half_dome.jpg');
https://my_account.snowflakecomputing.com/api/files/my_db.public.images_stage/us/yosemite/half_dome.jpg