Is there a way to restrict a particular user from making any modification on particular table.
I am thinking to create a Instead of trigger and some how get the login info and restrict the user from running delete/update statements.
But is there any better way to do this, like Sql server has some login permission setting to restrict this
I'd revoke all privileges first (assuming you already have the user)
REVOKE ALL
ON {object_name}
FROM {user_name}
Then grant only SELECT to that user.
GRANT SELECT, INSERT
ON {object_name}
TO {user_name}
Related
I am trying to create a read all user for my database, but it seems the most simplest of queries isn't working properly.
When I try running the query select * from public.reports limit 5; it works fine when using the postgres user (db owner), returning 5 lines of results. However, it returns no results when using this new user. It throws no errors, it says nothing. It simply returns no results, as if the table was empty.
I created the new user using the following queries:
CREATE USER "new_user" WITH PASSWORD 'strong_password';
GRANT CONNECT ON DATABASE my_database TO "new_user";
GRANT USAGE ON SCHEMA public TO "new_user";
GRANT SELECT ON ALL SEQUENCES IN SCHEMA public TO "new_user";
GRANT SELECT ON ALL TABLES IN SCHEMA public to "new_user";
ALTER USER "new_user" WITH LOGIN;
What am I missing?
So you have row-level security enabled? The manual:
If row-level security is enabled for a table, but no applicable
policies exist, a “default deny” policy is assumed, so that no rows
will be visible or updatable.
This would explain that your user cannot see any rows.
The simplest way to bypass RLS generally for the new user is with BYPASSRLS.
CREATE USER new_user WITH BYPASSRLS PASSWORD 'strong_password';
Else, you need CREATE POLICY to allow things. To allow all read and write operations on table reports for our new role:
CREATE POLICY foo ON public.reports TO new_user USING (true) WITH CHECK (true);
I am a big fan of PostgreSQL but can't figure out one aspects of it's built in user management.
My problem is that I have set up pgAdmin and will have some non-developers manually update data in some specific tables. For this reason I have created a new user called "admin" and are looking to restrict this users rights.
I have tried to delete all rights for the user with the following query (from another user):
REVOKE ALL PRIVILEGES ON ALL TABLES IN SCHEMA public FROM admin;
REVOKE ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA public FROM admin;
REVOKE ALL PRIVILEGES ON ALL FUNCTIONS IN SCHEMA public FROM admin;
The above did lead to the following error when I wrote a simple SELECT statement from the user admin on a table called "crap": ERROR: permission denied for relation crap.
But what I was able to do with the user admin which by now shouldn't have any rights was the following: DROP TABLE crap; which worked!?
I am really surprised by this. This user is not a Postgres superuser. How can I remove this right to drop tables for a specific user?
You're one level off in hierarchy for the permissions.
REVOKE ALL PRIVILEGES FROM SCHEMA public FROM <role_name>;
You were affecting permissions within the table. You must also go one level up to the schema as well to protect create/drop access. You may also want to revoke access at the database level as well to protect the schema.
REVOKE ALL PRIVILEGES FROM DATABASE <database_name> FROM <role_name>;
You could also simply remove the user. Alternatively you could simply disable that user's ability to login.
ALTER ROLE <role_name> SET NOLOGIN;
If these don't work for you, you can go down a somewhat more complicated route and make an event trigger that watches for DROP TABLE events, compares against the role, and either allows it to continue or aborts the transaction.
CREATE OR REPLACE FUNCTION no_admin_drop()
RETURNS event_trigger LANGUAGE plpgsql AS $$
BEGIN
IF CURRENT_USER = 'admin'::regrole THEN
RAISE EXCEPTION 'command is disabled';
END IF;
END;
$$;
CREATE EVENT TRIGGER no_admin_drop ON sql_drop
EXECUTE FUNCTION no_admin_drop();
I have a group login which has the Server Role "dbcreator". Users of this login has been granted execute on "sp_delete_database_backuphistory" so that they can delete each others databases. The problem now is that it is possible for these users to delete databases created by other logins. Is there a solution for this? Can permission´s be set, so that these users ONLY can delete databases created with this login?
You can't do this directly, but you can wrap the system sp_delete_database_backuphistory into your own usp_delete_database_backuphistory
that can call sp_delete_database_backuphistory or return immediately depending on a result of the check you want to perform.
I cannot ask you in a comment what do you mean saying 'databases created by other users', first of all only login (not user) can create a database but this information (db creator) you cannot extract from any system metadata, all you can get is the current database owner and this can differ from database creator.
I mean, when you create a database you can explicitly assign other login to own the database, or you can do this later for certain purposes
I am connecting to my SQL studio manager using Power BI (a report writing software). I only want tables appearing listed under a certain schema, and deny permission to access all others, instead of displaying all tables which it currently does.
Usually, when preventing individual users from accessing a schema, I would use the following code:
revoke select on schema::UnwantedSchema to User
grant select on schema::WantedSchema To User
However, now I want it so ALL users and Logins have these permission settings. Not just the individual user. Is there a way I can do this without having to set the permissions for every individual user?
If you wanted to set the privileges to multiple user logins, You need to create a role and assign the role to the ers to that role. The give required permission to the role created.
Following are the sample steps.
--Create a new role
EXEC sp_addrole 'yourRole'
GO
--Assiging role to the user
EXEC sp_addrolemember 'yourRole', 'yourUser';
GO
--Assigning permissions to the Role
GRANT ALTER, DELETE, EXECUTE, INSERT, REFERENCES, SELECT,
UPDATE, VIEW DEFINITION ON SCHEMA::YourSchema TO yourRole;
GO
GRANT CREATE TABLE, CREATE PROCEDURE, CREATE FUNCTION, CREATE VIEW TO yourRole;
GO
I am having trouble adding a user to a test database I set up on my local machine. I have added the user fine but the user does not have permission to SELECT (Or anything else for that matter) on the database. I have tried gone the the permission tab under the server, the database, and the table (there is only one it is a very simple database just for testing) and selected grant for every single option yet it still does not work. I have also tried doing a Transact-SQL command like:
use testing
GRANT SELECT, UPDATE, DELETE, INSERT TO User
and a couple of other combinations that return successfully but I still do not have permission to select data from the table. Any suggestions?
Add the user to the db_datareader role to give the user select access to all of the tables.
Add the user to the public database role and they should be able to SELECT against the database (unless you have changed the public role's permissions).