Understanding Snowflake Privileges
In Snowflake, privileges are an essential aspect of managing access control. Privileges define what actions users can perform on specific database objects, such as tables, views, schemas, and databases. By assigning and managing privileges effectively, you ensure that your data remains secure while users have the necessary permissions to perform their tasks.

In this blog, we’ll explore the key concepts behind Snowflake privileges, common types of privileges, and how to grant and manage them.

1. What Are Privileges in Snowflake?
A privilege in Snowflake refers to a specific permission that allows a user or role to perform actions on a database object. These actions can range from querying data to creating, altering, or dropping objects within the database. Privileges are typically granted to roles, which are then assigned to users.

Key Privilege Types:

Database Privileges: Control access to entire databases.
Schema Privileges: Govern access to schemas within a database.
Table Privileges: Define actions allowed on tables and views.
Warehouse Privileges: Control access to compute resources.

1. Common Snowflake Privileges

Here are some of the most commonly used privileges in Snowflake, categorized by object type:

a. Database Privileges
CREATE SCHEMA: Allows the creation of schemas within a database.
MODIFY: Permits the modification of database properties.
USAGE: Grants basic access to the database without the ability to query data or make changes.
b. Schema Privileges
CREATE TABLE: Allows the creation of tables within a schema.
MODIFY: Allows modifications to schema properties.
USAGE: Grants access to use the schema but not directly query or modify its objects.
c. Table Privileges
SELECT: Allows querying data from a table or view.
INSERT: Grants the ability to insert new rows into a table.
UPDATE: Allows updating existing rows.
DELETE: Permits deleting rows from a table.
REFERENCES: Allows the creation of foreign keys that reference the table.
d. View Privileges
SELECT: Allows querying the data from a view.
REFERENCES: Permits referencing the view in other objects, such as foreign keys or stored procedures.
e. Warehouse Privileges
USAGE: Grants access to use the warehouse for running queries.
OPERATE: Allows starting and stopping a warehouse.

3. Granting Privileges in Snowflake

To manage privileges in Snowflake, you typically use the GRANT and REVOKE commands. The GRANT command assigns a specific privilege to a role, while the REVOKE command removes the privilege.

a. Granting a Privilege
To grant a privilege to a role, the following syntax is used:

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GRANT ON TO ROLE ;
For example, to grant the SELECT privilege on a table called employees to a role named analyst_role:

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GRANT SELECT ON TABLE employees TO ROLE analyst_role;
b. Revoking a Privilege
To revoke a previously granted privilege, use the following syntax:

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REVOKE ON FROM ROLE ;
For instance, to revoke the SELECT privilege from the analyst_role on the employees table:

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REVOKE SELECT ON TABLE employees FROM ROLE analyst_role;
c. Granting Privileges on Future Objects
Snowflake also allows you to grant privileges on future objects that haven’t been created yet. This is useful when you want a role to automatically inherit privileges for new tables, views, or schemas.

For example, to grant SELECT privileges on all future tables in a schema:

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GRANT SELECT ON FUTURE TABLES IN SCHEMA my_database.my_schema TO ROLE analyst_role;

4. Managing Privileges with Roles

In Snowflake, privileges are usually assigned to roles rather than directly to users. Roles are then assigned to users to grant them the necessary permissions. This simplifies privilege management, especially in larger organizations where multiple users need access to the same resources.

a. Creating a Role
To create a role, use the following SQL command:

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CREATE ROLE analyst_role;
b. Granting a Role to a User
Once a role is created, you can assign it to a user:

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GRANT ROLE analyst_role TO USER john_doe;
c. Granting Roles to Other Roles
You can also grant roles to other roles, creating a role hierarchy. This is helpful for managing large sets of privileges across multiple roles.

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GRANT ROLE analyst_role TO ROLE senior_analyst_role;

5. Monitoring Privileges

Snowflake provides a variety of information schema views to help you monitor and audit privileges in your account. Some useful views include:

GRANTS_TO_ROLES: Lists all privileges granted to roles.
GRANTS_TO_USERS: Shows all privileges assigned to users.
OBJECT_PRIVILEGES: Displays privileges granted on specific objects.
For example, to view all privileges granted on a specific table:

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SELECT * FROM SNOWFLAKE.ACCOUNT_USAGE.OBJECT_PRIVILEGES WHERE object_name = 'employees';

6. Best Practices for Managing Privileges

Grant Privileges at the Role Level: Avoid granting privileges directly to users. Instead, use roles to group and manage privileges.
Use the Principle of Least Privilege: Only grant the minimum privileges necessary for a user or role to perform their tasks.
Regularly Audit Privileges: Periodically review and audit privileges using Snowflake’s information schema to ensure users and roles have appropriate access.
Leverage Future Privileges: Use future privilege grants to automatically manage access for newly created objects, reducing manual overhead.

Conclusion

Effective privilege management in Snowflake is crucial for maintaining data security, ensuring users have the appropriate access to resources, and optimizing administrative control. By understanding how to manage Snowflake privileges — including granting, revoking, and monitoring them — you can create a well-structured and secure environment in your Snowflake account. This approach helps ensure that users only access the data they need, while also providing administrators with the necessary control to safeguard sensitive information.