I created a foreign data wrapper and created the user mappings for 2 users one is admin and the other only has readonly access to the tables.
When I try to query using the readonly user I get an error:
ERROR: permission denied for schema testing LINE 1: SELECT * FROM testing.bldg ^ ********** Error ********** ERROR: permission denied for schema testing SQL state: 42501 Character: 15
Here is my setup:
Postgres 9.6.1 in Amazon RDS, both DBs are part of same AWS RDS instance.
When I connect to remote database directly using the readonly user I am able to query the table, problem only happens when using the fdw.
As the readonly use when I query this "select * from pg_foreign_table;"
I see all the foreign tables.
I have tried the following:
grant usage on schema ...
grant select on table...
GRANT USAGE ON FOREIGN SERVER ...
Any ideas.
I was able to resolve the issue, here are the steps:
create readonly user on local DB
create readonly user on remote DB
create fdw and user mapping for readonly user
grant usage privs on remote and local db (I was missing this on local)
grant select privs on local and remote db to readonly user.
Related
I just installed a new Postgresql 15 server on Debian 11 and configured postgresql.conf to allow remote connections by un-commenting the following line.
listen_addresses = '*'
I also created a new user and database using the commands below
su postgres psql
postgres=# create database exampledomain;
postgres=# create user exampledomain with encrypted password 'mypassword';
postgres=# grant all privileges on database exampledomain to exampledomain;
I also added the following line to pg_hba.conf so the new user can connect from a remote connection
host exampledomain exampledomain 0.0.0.0/0 md5
I am able to connect to the exampledomain database using username "exampledomain". However when trying to create a new table under the public schema using DBeaver
CREATE TABLE public.newtable (
id varchar NULL
);
I get the following message
ERROR: permission denied for schema public
Position: 14
With older versions of Postgresql, that's all the steps I had to do in order to create tables. With Postgresql 15 do I need to any additional steps?
With Postgresql 15 do I need to any additional steps?
Yes. Postgres 15 changed the permissions on the public schema for security reasons:
Quote from the release notes
Remove PUBLIC creation permission on the public schema (Noah Misch)
The new default is one of the secure schema usage patterns that Section 5.9.6 has recommended since the security release for CVE-2018-1058. The change applies to new database clusters and to newly-created databases in existing clusters. Upgrading a cluster or restoring a database dump will preserve public's existing permissions.
For existing databases, especially those having multiple users, consider revoking CREATE permission on the public schema to adopt this new default. For new databases having no need to defend against insider threats, granting CREATE permission will yield the behavior of prior releases.
So if you want a user to be able to create table in the public schema, you need to grant those privileges:
grant usage,create on schema public to exampledomain
what's the recommended way to provide readonly access to all databases in postgresql version 12.
I am using this found at How do you create a read-only user in PostgreSQL?
CREATE ROLE readaccess;
CREATE USER my_user_test WITH PASSWORD 'my_user_test';
GRANT readaccess TO my_user_test;
\c database_name;
-- need to connect to the database first on which we need to execute the below commands
GRANT CONNECT ON DATABASE database_name TO readaccess;
GRANT USAGE ON SCHEMA public TO readaccess;
GRANT SELECT ON ALL TABLES IN SCHEMA public TO readaccess;
-- Assign permissions to read all newly tables created in the future
ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO readaccess;
But using this approach I need to individually connect to each database and provide the role read only access.
Is there a better approach to provide a read only access all existing databases at once?
Thanks.
created a postgresql instance on AWS with the username ziggy. I restored a database to that instance. however I cannot even select any of the tables
select * FROM mac_childcare_parcels
gives me ERROR: permission denied for relation mac_childcare_parcels
********** Error **********
the owner of that table belongs to the postgres login.
so i tried running this: grant all privileges on all tables in schema public to ziggy but since I am not a superuser I cannot give myself privileges so that throws a permissions error. what do I have to do to get access to the tables?
this does not work either
grant select on mac_childcare_parcels to ziggy
this query returns successful but does not let the login ziggy access the tables
GRANT USAGE ON SCHEMA public TO ziggy;
First login with superuser and provide all rds superuser access to the newly created user using a command like below
GRANT rds_superuser TO ziggy;
replace rds_superuser with your rds superuser.
You need to also GRANT USAGE on the SCHEMA, e.g.
GRANT USAGE ON SCHEMA public TO ziggy;
The superuser access is needed to run the access level queries. But as you said that access is not present then i would say copy the replica of the db which you have restored from backup and grant yourself as superuser.
then provide all needed access to any users.
I had a foreign table set up in Postgres 10. The role "role1" has been granted usage on the foreign server (fs) that was set up using the postgres superuser.
I imported the table using the import schema command:
IMPORT FOREIGN SCHEMA f_schema LIMIT TO (my_fdw_table) FROM fs INTO ls;
That worked fine.
However, when I try to query the table I get the following error:
SELECT * FROM my_fdw_table LIMIT 1;
ERROR: permission denied for view my_fdw_table
CONTEXT: remote SQL command: ...
My understanding is that FDW should treat views and tables the same.
It looks like the remote user that you used in the user mapping for your local user and the foreign server does not have the required permissions on the table (or the schema that contains it).
User "role1" should create user mapping for itself like:
CREATE USER MAPPING FOR role1 SERVER fs OPTIONS (USER 'role1', PASSWORD 'password1');
IMPORT FOREIGN SCHEMA f_schema LIMIT TO (my_fdw_table) FROM SERVER fs INTO ls;
Also, if "role1" is not an owner of the database, it should get access from its owner:
GRANT USAGE ON SCHEMA ls TO role1;
Assuming ls is local schema.
I need to restrict a user, access only on a particualr schema tables only.So I tried following query and login as user1_gmail_com. But I got following error when I try to browse any schema table.
My Query:
SELECT clone_schema('my_application_template_schema','user1_gmail_com');
CREATE USER user1_gmail_com WITH PASSWORD 'myloginpassword';
REVOKE ALL ON ALL TABLES IN SCHEMA user1_gmail_com FROM PUBLIC;
GRANT SELECT ON ALL TABLES IN SCHEMA user1_gmail_com TO user1_gmail_com;
SQL error:
ERROR: permission denied for schema user1_gmail_com at character 46
In statement:
SELECT COUNT(*) AS total FROM (SELECT * FROM "user1_gmail_com"."organisations_table") AS sub
Updated Working Query:
SELECT clone_schema('my_application_template_schema','user1_gmail_com');
CREATE USER user1_gmail_com WITH PASSWORD 'myloginpassword';
REVOKE ALL ON ALL TABLES IN SCHEMA user1_gmail_com FROM PUBLIC;
GRANT USAGE ON SCHEMA user1_gmail_com TO user1_gmail_com;
GRANT SELECT ON ALL TABLES IN SCHEMA user1_gmail_com TO user1_gmail_com;
You need to grant access not only to the tables in the schema, but also to the schema itself.
From the manual:
By default, users cannot access any objects in schemas they do not own. To allow that, the owner of the schema must grant the USAGE privilege on the schema.
So either make your created user the owner of the schema, or grant USAGE on the schema to this user.
This confused me. Still not sure I'm handling it correctly. Run \h grant for the syntax within psql. Here is how I managed to get my other users and groups to work as I needed:
GRANT ALL PRIVILEGES ON SCHEMA foo TO GROUP bar;
GRANT ALL PRIVILEGES ON ALL TABLES IN SCHEMA foo TO GROUP bar;
I kept getting this error when using flyway to deploy database changes. I do some manual setup first, such as creating the database, so flyway wouldn't need those super-admin permissions.
My Fix
I had to ensure that the database user that flyway job used had ownership rights to the public schema, so that the flyway user could then assign the right to use the schema to other roles.
Additional setup Details
I am using AWS RDS (both regular and Aurora), and they don't allow super users in the databases. RDS reserves super users for use by AWS, only, so that consumers are unable to break the replication stuff that is built in. However, there's a catch-22 that you must be an owner in postgres to be able to modify it.
My solution was to create a role that acts as the owner ('owner role'), and then assign both my admin user and the flyway user to the owner role, and use ALTER scripts for each object to assign the object's owner to the owner role.
I missed the public schema, since that was auto-created when I created the database script manually. The public schema defaulted to my admin role rather than the shared owner role. So when the flyway user tried to assign public schema permissions to other roles, it didn't have the authority to do that. An error was not thrown during flyway execution, however.