For directory tables, a named external stage allows for the automatic refreshing of metadata. This capability is particularly useful when dealing with files stored on external storage services (like Amazon S3, Google Cloud Storage, or Azure Blob Storage) and accessed through Snowflake. The external stage references these files, and the directory table's metadata can be automatically updated to reflect changes in the underlying files.
References:
* Snowflake Documentation: External Stages

A Scoped URL permits temporary access to a staged file without the need to grant privileges to the stage or to issue access tokens. It provides a secure way to share access to files stored in Snowflake

The Snowflake command to unload the result of a query to a single file is COPY INTO <internal stage> with SINGLE = TRUE followed by a GET command to download the file. This command unloads the query result into a single file in the specified internal stage

In Snowflake, a user with the SECURITYADMIN role or higher can activate and enforce a network policy for all users in an account. Additionally, a role that has ownership of the network policy can also activate and enforce it