Access Control Considerations

This topic provides best practices and important considerations for managing secure access to your Snowflake account and data stored within the account. In particular, it provides general guidance for configuring role-based access control, which limits access to objects based on a user’s role.

In this Topic:

Using the ACCOUNTADMIN Role

The account administrator (i.e users with the ACCOUNTADMIN system role) role is the most powerful role in the system. This role alone is responsible for configuring parameters at the account level. Users with the ACCOUNTADMIN role can view and operate on all objects in the account, can view and manage Snowflake billing and credit data, and can stop any running SQL statements.

In the default access control hierarchy, the other administrator roles are children of this role:

  • The user administrator (USERADMIN) role includes the privileges to create and manage users and roles (assuming ownership of those roles or users has not been transferred to another role).

  • The security administrator (i.e users with the SECURITYADMIN system role) role includes the global MANAGE GRANTS privilege to grant or revoke privileges on objects in the account. The USERADMIN role is a child of this role in the default access control hierarchy.

  • The system administrator (SYSADMIN) role includes the privileges to create warehouses, databases, and all database objects (schemas, tables, etc.).

Attention

By default, when your account is provisioned, the first user is assigned the ACCOUNTADMIN role. This user should then create one or more additional users who are assigned the USERADMIN role. All remaining users should be created by the user(s) with the USERADMIN role.

Control the Assignment of the ACCOUNTADMIN Role to Users

We strongly recommend the following precautions when assigning the ACCOUNTADMIN role to users:

  • Assign this role only to a select/limited number of people in your organization.

  • All users assigned the ACCOUNTADMIN role should also be required to use multi-factor authentication (MFA) for login (for details, see Configuring Access Control).

  • Assign this role to at least two users. We follow strict security procedures for resetting a forgotten or lost password for users with the ACCOUNTADMIN role. These procedures can take up to two business days. Assigning the ACCOUNTADMIN role to more than one user avoids having to go through these procedures because the users can reset each other’s passwords.

Tip

It also helps if you associate an actual person’s email address to ACCOUNTADMIN users, so that Snowflake Support knows who to contact in an urgent situation.

Avoid Using the ACCOUNTADMIN Role to Create Objects

The ACCOUNTADMIN role is intended for performing initial setup tasks in the system and managing account-level objects and tasks on a day-to-day basis. As such, it should not be used to create objects in your account, unless you absolutely need these objects to have the highest level of secure access. If you create objects with the ACCOUNTADMIN role and you want users to have access to these objects, you must explicitly grant privileges on the objects to the roles for these users.

Instead, we recommend creating a hierarchy of roles aligned with business functions in your organization and ultimately assigning these roles to the SYSADMIN role. For more information, see Aligning Object Access with Business Functions in this topic.

Tip

To help prevent account administrators from inadvertently using the ACCOUNTADMIN role to create objects, assign these users additional roles and designate one of these roles as their default (i.e. do not make ACCOUNTADMIN the default role for any users in the system).

This doesn’t prevent them from using the ACCOUNTADMIN role to create objects, but it forces them to explicitly change their role to ACCOUNTADMIN each time they log in. This can help make them aware of the purpose/function of roles in the system and encourage them to change to the appropriate role for performing a given task, particularly when they need to perform account administrator tasks.

Avoid Using the ACCOUNTADMIN Role for Automated Scripts

We recommend using a role other than ACCOUNTADMIN for automated scripts. If, as recommended, you create a role hierarchy under the SYSADMIN role, all warehouse and database object operations can be performed using the SYSADMIN role or lower roles in the hierarchy. The only limitations you would encounter is creating or modifying users or roles. These operations must be performed by a user with the SECURITYADMIN role or another role with sufficient object privileges.

Accessing Database Objects

All securable database objects (such as TABLE, FUNCTION, FILE FORMAT, STAGE, SEQUENCE, etc.) are contained within a SCHEMA object within a DATABASE. As a result, to access database objects, in addition to the privileges on the specific database objects, users must be granted the USAGE privilege on the container database and schema.

For example, suppose mytable is created in mydb.myschema. In order to query mytable, a user must have the following privileges at a minimum:

Database

USAGE on mydb

Schema

USAGE on myschema

Table

SELECT on mytable

Managing Custom Roles

When a custom role is first created, it exists in isolation. The role must be assigned to any users who will use the object privileges associated with the role. The custom role must also be granted to any roles that will manage the objects created by the custom role.

Important

By default, not even the ACCOUNTADMIN role can modify or drop objects created by a custom role. The custom role must be granted to the ACCOUNTADMIN role directly or, preferably, to another role in a hierarchy with the SYSADMIN role as the parent. The SYSADMIN role is managed by the ACCOUNTADMIN role.

For instructions to create a role hierarchy, see Creating a Role Hierarchy.

Aligning Object Access with Business Functions

Consider taking advantage of role hierarchies to align access to database objects with business functions in your organization. In a role hierarchy, roles are granted to other roles to form an inheritance relationship. Permissions granted to roles at a lower level are inherited by roles at a higher level.

For optimal flexibility in controlling access to database objects, create a combination of object access roles with different permissions on objects and assign them as appropriate to functional roles:

  • Grant permissions on database objects or account objects (such as warehouses) to access roles.

  • Grant access roles to functional roles to create a role hierarchy. These roles correspond to the business functions of your organization and serve as a catch-all for any access roles required for these functions.

    When appropriate, grant lower-level functional roles to higher-level functional roles in a parent-child relationship where the parent roles map to business functions that should subsume the permissions of the child roles.

    Following best practices for role hierarchies, grant the highest-level functional roles in a role hierarchy to the system administrator (SYSADMIN) role. System administrators can then grant privileges on database objects to any roles in this hierarchy:

Note

There is no technical difference between an object access role and a functional role in Snowflake. The difference is in how they are used logically to assemble and assign sets of permissions to groups of users.

Example

As a simple example, suppose two databases in an account, fin and hr, contain payroll and employee data, respectively. Accountants and analysts in your organization require different permissions on the objects in these databases to perform their business functions. Accountants should have read-write access to fin but might only require read-only access to hr because human resources personnel maintain the data in this database. Analysts could require read-only access to both databases.

Permissions on existing database objects are granted via the following hierarchy of access roles and functional roles:

Note

When new objects are added in each database, consider automatically granting privileges on the objects to roles based on object type (e.g. schemas, tables, or views). For information, see Simplifying Grant Management Using Future Grants (in this topic).

Custom Role

Permissions

Description

db_hr_r

Access role that permits read-only access to tables in the hr database.

USAGE on database hr.

USAGE on all schemas in database hr.

SELECT on all tables in database hr.

db_fin_r

Access role that permits read-only access to tables in the fin database.

USAGE on database fin.

USAGE on all schemas in database fin.

SELECT on all tables in database fin.

db_fin_rw

Access role that permits read-write access to tables in the fin database.

USAGE on database fin.

USAGE on all schemas in database fin.

SELECT, INSERT, UPDATE, DELETE on all tables in database fin.

accountant

Functional role for accountants in your organization.

N/A

analyst

Functional role for analysts in your organization.

N/A

The following diagram shows the role hierarchy for this example:

Example: Hierarchy of access and functional roles

To configure access control for this example:

  1. As a user administrator (user with the USERADMIN role) or another role with the CREATE ROLE privilege on the account, create the access roles and functional roles in this example:

    CREATE ROLE db_hr_r;
    CREATE ROLE db_fin_r;
    CREATE ROLE db_fin_rw;
    CREATE ROLE accountant;
    CREATE ROLE analyst;
    
  2. As a security administrator (user with the SECURITYADMIN role) or another role with the MANAGE GRANTS privilege on the account, grant the required minimum permissions to each of the access roles:

    -- Grant read-only permissions on database HR to db_hr_r role.
    GRANT USAGE ON DATABASE hr TO ROLE db_hr_r;
    GRANT USAGE ON ALL SCHEMAS IN DATABASE hr TO ROLE db_hr_r;
    GRANT SELECT ON ALL TABLES IN DATABASE hr TO ROLE db_hr_r;
    
    -- Grant read-only permissions on database FIN to db_fin_r role.
    GRANT USAGE ON DATABASE fin TO ROLE db_fin_r;
    GRANT USAGE ON ALL SCHEMAS IN DATABASE fin TO ROLE db_fin_r;
    GRANT SELECT ON ALL TABLES IN DATABASE fin TO ROLE db_fin_r;
    
    -- Grant read-write permissions on database FIN to db_fin_rw role.
    GRANT USAGE ON DATABASE fin TO ROLE db_fin_rw;
    GRANT USAGE ON ALL SCHEMAS IN DATABASE fin TO ROLE db_fin_rw;
    GRANT SELECT,INSERT,UPDATE,DELETE ON ALL TABLES IN DATABASE fin TO ROLE db_fin_rw;
    
  3. As a security administrator (user with the SECURITYADMIN role) or another role with the MANAGE GRANTS privilege on the account, grant the db_fin_rw access role to the accountant functional role, and grant the db_hr_r db_fin_r access roles to the analyst functional role:

    GRANT ROLE db_fin_rw TO ROLE accountant;
    GRANT ROLE db_hr_r TO ROLE analyst;
    GRANT ROLE db_fin_r TO ROLE analyst;
    
  4. As a security administrator (user with the SECURITYADMIN role) or another role with the MANAGE GRANTS privilege on the account, grant both the analyst and accountant roles to the system administrator (SYSADMIN) role:

    GRANT ROLE accountant,analyst TO ROLE sysadmin;
    
  5. As a security administrator (user with the SECURITYADMIN role) or another role with the MANAGE GRANTS privilege on the account, grant the business functional roles to the users who perform those business functions in your organization. In this example, the analyst functional role is granted to user user1, and the accountant functional role is granted to user user2.

    GRANT ROLE accountant TO USER user1;
    GRANT ROLE analyst TO USER user2;
    

Centralizing Grant Management Using Managed Access Schemas

With regular (i.e. non-managed) schemas in a database, object owners (i.e. roles with the OWNERSHIP privilege on one or more objects) can grant access on those objects to other roles, with the option to further grant those roles the ability to manage object grants.

To further lock down object security, consider using managed access schemas. In a managed access schema, object owners lose the ability to make grant decisions. Only the schema owner (i.e. the role with the OWNERSHIP privilege on the schema) or a role with the MANAGE GRANTS privilege can grant privileges on objects in the schema, including future grants, centralizing privilege management.

For more information on managed access schemas, see Creating Managed Access Schemas.

Simplifying Grant Management Using Future Grants

Future grants allow defining an initial set of privileges on objects of a certain type (e.g. tables or views) in a specified schema. As new objects are created, the defined privileges are automatically granted to a role, simplifying grant management.

Consider the following scenario, in which a particular role is granted the SELECT privilege on all new tables created in schema. At a later date, the decision is made to revoke the privilege from this role and instead grant it to a different role. Using the ON FUTURE keywords for new tables and the ALL keyword for existing tables, few SQL statements are required to grant and revoke privileges on new and existing tables. For example:

-- Grant the SELECT privilege on all new (i.e. future) tables in a schema to role R1
GRANT SELECT ON FUTURE TABLES IN SCHEMA s1 TO ROLE r1;

-- / Create tables in the schema /

-- Grant the SELECT privilege on all new tables in a schema to role R2
GRANT SELECT ON FUTURE TABLES IN SCHEMA s1 TO ROLE r2;

-- Grant the SELECT privilege on all existing tables in a schema to role R2
GRANT SELECT ON ALL TABLES IN SCHEMA s1 TO ROLE r2;

-- Revoke the SELECT privilege on all new tables in a schema (i.e. future grant) from role R1
REVOKE SELECT ON FUTURE TABLES IN SCHEMA s1 FROM ROLE r1;

-- Revoke the SELECT privilege on all existing tables in a schema from role R1
REVOKE SELECT ON ALL TABLES IN SCHEMA s1 FROM ROLE r1;

For more information on future grants, see Assigning Future Grants on Objects.

Viewing Query Results

A user cannot view the result set from a query that another user executed. This behavior is intentional. For security reasons, only the user who executed a query can access the query results.

Note

This behavior is not connected to the Snowflake access control model for objects. Even a user with the ACCOUNTADMIN role cannot view the results for a query run by another user.

Understanding Cloned Objects and Granted Privileges

Cloning a database, schema or table creates a copy of the source object. The cloned object includes a snapshot of data present in the source object when the clone was created.

A cloned object is considered a new object in Snowflake. Any privileges granted on the source object do not transfer to the cloned object. However, a cloned container object (a database or schema) retains any privileges granted on the objects contained in the source object. For example, a cloned schema retains any privileges granted on the tables, views, UDFs, and other objects in the source schema.

For more details about cloning, see Cloning Considerations and CREATE <object> … CLONE.