How to Grant Usage on All Schemas in Redshift

Redshift is a cloud-based data warehouse service that allows you to store and query large amounts of data using SQL. You can use Redshift to create databases, schemas, tables, views, functions, and other objects to organize and analyze your data.

One of the tasks you may want to do is to grant usage on all schemas in Redshift. This can help you give access to users or groups to view and query the objects in all schemas, without granting them other privileges such as creating or dropping objects. You can grant usage on all schemas in Redshift using the GRANT command with the ON SCHEMA option.

In this blog post, we will show you how to grant usage on all schemas in Redshift using the GRANT command. We will also explain some of the benefits and limitations of granting usage on all schemas in Redshift.

How to Grant Usage on All Schemas in Redshift?

To grant usage on all schemas in Redshift, you need to have the following:

A Redshift database that contains one or more schemas that you want to grant usage on.
A user or group that you want to grant usage on all schemas to.
A user or role that has the privilege to grant usage on all schemas. This can be the owner of the database, a superuser, or a user or role that has been granted the GRANT OPTION.

The steps to grant usage on all schemas in Redshift are as follows:

Connect to the Redshift database using a client tool or application that supports SQL commands. For example, you can use the psql command-line tool, the AWS CLI, or the AWS Management Console.
Run the GRANT command with the ON SCHEMA option using the following syntax:

GRANT USAGE ON SCHEMA schema_name [, ...] TO { username | GROUP group_name | PUBLIC } [, ...];

1 2	GRANT USAGE ON SCHEMA schema_name [, ...] TO { username \| GROUP group_name \| PUBLIC } [, ...];

This command grants usage on one or more schemas to one or more users, groups, or public. For example, you can use the following command:

GRANT USAGE ON SCHEMA public, sales, marketing TO GROUP analysts;

1 2	GRANT USAGE ON SCHEMA public, sales, marketing TO GROUP analysts;

This command grants usage on the public, sales, and marketing schemas to the analysts group.

Optionally, you can also grant usage on all tables in all schemas using the following syntax:

GRANT SELECT ON ALL TABLES IN SCHEMA schema_name [, ...] TO { username | GROUP group_name | PUBLIC } [, ...];

1 2	GRANT SELECT ON ALL TABLES IN SCHEMA schema_name [, ...] TO { username \| GROUP group_name \| PUBLIC } [, ...];

This command grants select (read-only) privilege on all tables in one or more schemas to one or more users, groups, or public. For example, you can use the following command:

GRANT SELECT ON ALL TABLES IN SCHEMA public, sales, marketing TO GROUP analysts;

1 2	GRANT SELECT ON ALL TABLES IN SCHEMA public, sales, marketing TO GROUP analysts;

This command grants select privilege on all tables in the public, sales, and marketing schemas to the analysts group.

Optionally, you can also grant usage on all functions and procedures in all schemas using the following syntax:

GRANT EXECUTE ON ALL { FUNCTIONS | PROCEDURES } IN SCHEMA schema_name [, ...] TO { username | GROUP group_name | PUBLIC } [, ...];

1 2	GRANT EXECUTE ON ALL { FUNCTIONS \| PROCEDURES } IN SCHEMA schema_name [, ...] TO { username \| GROUP group_name \| PUBLIC } [, ...];

This command grants execute privilege on all functions or procedures in one or more schemas to one or more users, groups, or public. For example, you can use the following command:

GRANT EXECUTE ON ALL FUNCTIONS IN SCHEMA public, sales, marketing TO GROUP analysts;

1 2	GRANT EXECUTE ON ALL FUNCTIONS IN SCHEMA public, sales, marketing TO GROUP analysts;

This command grants execute privilege on all functions in the public, sales, and marketing schemas to the analysts group.

What are the Benefits and Limitations of Granting Usage on All Schemas in Redshift?

Granting usage on all schemas in Redshift has some benefits and limitations that you need to be aware of when using it. Some of them are:

Benefits:
- You can grant usage on all schemas in Redshift using a single command, which can save time and effort.
- You can grant usage on all schemas in Redshift without granting other privileges such as creating or dropping objects, which can improve security and prevent unauthorized changes.
- You can grant usage on all schemas in Redshift along with other privileges such as select or execute on all tables, functions, or procedures in all schemas, which can give more flexibility and control over access levels.
Limitations:
- You cannot grant usage on all schemas in Redshift for external schemas that are created using Redshift Spectrum. You need to grant usage on each external schema individually using a different syntax.
- You cannot grant usage on all schemas in Redshift for future schemas that are not yet created. You need to grant usage on each new schema after it is created using a separate command.
- You may incur some charges for granting usage on all schemas in Redshift. For example, you may be charged for the requests, the storage, and the data transfer.

Conclusion

In this blog post, we have shown you how to grant usage on all schemas in Redshift using the GRANT command with the ON SCHEMA option. We have also explained some of the benefits and limitations of granting usage on all schemas in Redshift.

We hope this post has helped you understand how to use Redshift to give access to users or groups to view and query the objects in all schemas without granting them other privileges. If you have any questions or feedback, please leave a comment below.