I am the admin of a PostgreSQL 11 DB on Azure.
Some of the users only have access to specific views.
The users were created by:
CREATE USER M1234 WITH PASSWORD '1234!';
GRANT USAGE ON SCHEMA public TO M1234;
GRANT SELECT ON table v_xxx TO M1234;
GRANT SELECT ON table v_yyy TO M1234;
For some reason the grant for select on one or all the existing views is removed every so often and the users of course cannot access.
I would really appreciate it if anyone has any insight as to why and how this could happen and if there is a more long term solution.
You grant SELECT on existing tables, but for future tables, you need additional permissions
-- Grant access to future tables ALTER DEFAULT PRIVILEGES IN SCHEMA a_given_schema GRANT SELECT ON TABLES TO read access;
Related
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 have a bit of a funny situation in Amazon Redshift where I have a user X who has grant select on all tables in schema public, but once a new table is created, this grant doesn't seem to apply to the new table. Is this normal behaviour? If yes, how does one deal with it such that the schema level grants are maintained. Thank you.
Executing the following command as super user (master):
alter default privileges
for user staging_user
in schema staging
grant select on tables
to reporting_user;
will allow reporting_user to select data from all future tables created by staging_user in schema staging.
In Redshift tables and views do not automatically inherit the permissions of their parent schema. Your newly created tables are only accessible to the user who created them, and the superuser.
In a recent patch to Redshift a new feature to grant default privileges was implemented that addresses this issue.
Alter Default Privileges
The following code snippet will grant select privileges only for all future tables in the sales schema to the sales_admin group. If you want this to apply to existing tables in a schema you will need to combine it with a second grant statement.
alter default privileges in schema sales grant select on tables to group sales_admin;
This is a normal behavior. Only the object owner/superuser have permission to use the object by default.
http://docs.aws.amazon.com/redshift/latest/dg/r_Privileges.html
You can add grant command to your create table statement and grant needed privileges for the user.
When we first spotted new tables not appearing in our reporting tool, I discovered a quick workaround is to re-execute the following SQL statement for the groups/users impacted:
ALTER DEFAULT PRIVILEGES IN SCHEMA <SCHEMANAME> GRANT SELECT ON TABLES TO GROUP <USER/GROUPNAME>;
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;
I have a multi-schema, multi-user Postgres DB. There is one table that I would like ALL users, both current and future, to be able to SELECT from.
I can GRANT SELECT to all current users... but how can I create a table that allows any future user to select? Is there a way to set table permissions, rather than granting user privileges?
A filesystem analogy would be using chmod to make a file to be readable by the public.
grant select on the_table to public;
From the manual:
The key word PUBLIC indicates that the privileges are to be granted to all roles, including those that might be created later. PUBLIC can be thought of as an implicitly defined group that always includes all roles
I have been looking for this for years and I have tried everything on the web with no success.
I am able to do it in MSSQL, but I didn´t find a way to do it in PostgreSQL.
What I want to achieve is just create a role with login that cannot create, drop or alter databases, functions, tables or anything else. Just select specific functions.
For example, if I have a table called costumer and two functions called return_customers() and return_time() I just want a role with login that are able to select return_customers() and select return_time(). Nothing more than that.
Thank you very much for supporting this useful web site!
Execute this connected to the database you want to configure.
-- Create the user.
CREATE ROLE somebody WITH LOGIN PASSWORD '...';
-- Prevent all authenticated users from being able to use the database,
-- unless they have been explicitly granted permission.
REVOKE ALL PRIVILEGES ON DATABASE foo FROM PUBLIC;
REVOKE ALL PRIVILEGES ON ALL TABLES IN SCHEMA public FROM PUBLIC;
REVOKE ALL PRIVILEGES ON ALL FUNCTIONS IN SCHEMA public FROM PUBLIC;
REVOKE ALL PRIVILEGES ON ALL SEQUENCES IN SCHEMA public FROM PUBLIC;
-- Allow the user to only use the specified functions.
GRANT CONNECT ON DATABASE foo TO somebody;
GRANT EXECUTE ON FUNCTION return_customers(), return_time() TO somebody;
If you have more schemas than "public" then you will need to add those to the two REVOKE ALL PRIVILEGES ON ALL ... statements.
Do not forget that the functions must have been created with SECURITY DEFINER or this user will still be unable to execute them, as the contents of the function will be executed with the permissions of this user, instead of the user who created the function.
See:
CREATE FUNCTION particularly SECURITY DEFINER
GRANT both for adding users to roles and for assigning access rights to tables, sequences, etc
REVOKE
CREATE ROLE