We are trying to create a user in Amazon Redshift which should only access a specific database. We know how to assign user to specific schema, but I want use public schema.
Till now we tried following commands:
To create user:
create user tt password 'tttt';
To create group:
create group report_group with user tt;
To grant access of database
grant select on DATABASE demo TO tt;
but its not allowing running select query and fails with
access denied to schema public
any suggestion in this.
You need the below two grants to the user or the group
GRANT USAGE ON SCHEMA public TO tt;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO tt;
GRANT SELECT, INSERT, UPDATE, DELETE
ON ALL TABLES IN SCHEMA public
TO GROUP report_group;
ALTER DEFAULT PRIVILEGES IN SCHEMA public
GRANT SELECT ON TABLES TO GROUP report_group;
Related
I have a Postgres database (PostgreSQL-Version 11), which has a lot schematas. Each schemata has a lot of tables. So, now I've got a user xyz, which should have readaccess to all of those schematas and all future ones. I found this gist, which explains how to create a readaccess group and how to add a user to this group:
-- Create a group
CREATE ROLE readaccess;
-- Grant access to existing tables
GRANT USAGE ON SCHEMA public TO readaccess;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO readaccess;
-- Grant access to future tables
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO readaccess;
-- Create a final user with password
CREATE USER tomek WITH PASSWORD 'secret';
GRANT readaccess TO xyz;
But this is only working for the public schemata. Lets assume, i create a new schemata called "new_schema", the user xyz don't have readaccess to this this schema.
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO readaccess;
is creating readaccess to all future tables inside a specific schemata, but not for future schematas.
Long story short: How can i give readaccess to all existing and future schematas for a specific user?
Logged in as the superuser, how can I grant user access to a specific table under a specific schema.
I tried this
GRANT SELECT on TABLE this_schema.my_table TO my_user
But when I login as my_user I can't select from the table. I don't want my_user to have access to any other tables in this_schema.
Is this possible?
Yes its possible.
You can use following command, to give select access of specific table to specific user.
GRANT SELECT on SCHEMA_NAME.TABLE_NAME TO USER_NAME;
NOTE: user still list and describe other tables in the given schema.
You need to grant usage on the schema as well
GRANT USAGE ON SCHEMA this_schema TO GROUP my_user;
Without creating user group, you can do:
GRANT SELECT ON TABLE my_table IN SCHEMA this_schema TO my_user;
I am facing an issue while creating a readonly users in RDS PostgreSQL 9.6. I am executing the following SQL commands:
---- ###### CREATE ROLE ################
CREATE ROLE readonlyrole_dev;
-- Grant access to existing tables
GRANT USAGE ON SCHEMA public TO readonlyrole_dev;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO readonlyrole_dev;
-- set the privileges that will be applied to objects created in the future.
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO readonlyrole_dev;
CREATE USER readonly_dev WITH PASSWORD 'welcome1';
GRANT readonlyrole_dev TO readonly_dev;
When I login with the readonly_dev user, it has privilege to create the new tables by default but I don't want to do that. I want to keep readonly_dev only a read only user.
Note: To revoke the access from the user I am executing
REVOKE CREATE ON SCHEMA public FROM PUBLIC;
which revokes create objects privilege to all old users as well. I only want to revoke create privilege from newly created user.
How can I do that?
You cannot do that, and it is not necessary either.
Just deny the user the CREATE permission on all schemas. You should use user groups for that - put all users who should have the privilege to create tables in a group that has the required privilege on the schema and revoke CREATE from PUBLIC.
If you insist that you must have this, try creating an event trigger that throws an exception whenever a certain user tries to create a table.
I want to allow a users assigned to a role to delete their own content in postgres but not content made by admins. I am new to database management and thought that the below would work but doesn't.
GRANT ALL ON ALL SEQUENCES IN SCHEMA public TO analyst;
GRANT ALL ON ALL TABLES IN SCHEMA public TO analyst;
You should use row level security. Docs : https://www.postgresql.org/docs/10/ddl-rowsecurity.html
Ex :
CREATE POLICY analyst_policy
ON public.mytable
USING (user = CURRENT_USER);
I have a database with a template_schema.I cloned this template schema and created a database user with password. I need to provide access to cloned schema only, for the created user.
SELECT clone_schema('my_template_schema','john_smith_gmail_com');
CREATE USER john_smith_gmail_com WITH PASSWORD 'mypassword';
Upto this Ok. Then I need to grant access to this user for this cloned schema(john_smith_gmail_com) only
Method :1
I tried to revoke all privileges on all tables of cloned schema(john_smith_gmail_com) for the user and grant select to the user. But my question is, can this user get SELECT access on other schema tables?
REVOKE ALL ON ALL TABLES IN SCHEMA john_smith_gmail_com FROM john_smith_gmail_com;
GRANT SELECT ON ALL TABLES IN SCHEMA john_smith_gmail_com TO john_smith_gmail_com;
Method :2
Create a role with only SELECT access and assign or grant this role to newly created user. If I do this, for which schema I grant access,because I clone schema dynamically?
Which method is best one?
From postgresql version 9.0 and forward, the best way is probably to use ALTER DEFAULT PRIVILEGES.
...the default privileges for any object type normally grant all grantable permissions to the object owner, and may grant some privileges to PUBLIC as well. However, this behavior can be changed by altering the global default privileges with ALTER DEFAULT PRIVILEGES.
So if all users like "john_smith_gmail_com" should only have SELECT access to tables in "their own" schema, after creating the schema and user, you can run:
ALTER DEFAULT PRIVILEGES IN SCHEMA john_smith_gmail_com GRANT SELECT ON TABLES TO john_smith_gmail_com;