How can I change a username in Informix?
select * from sysusers; lists below
username John.Doe
usertype R
priority 5
password
defrole admin
I want to update the username to be in lowercase for user john.doe but seems we cannot just run an update on it update sysusers set username = xxx as usual. What command should we use to do this?
Someone ran:
GRANT RESOURCE TO "John.Doe";
You will need to to revoke their RESOURCE privilege:
REVOKE RESOURCE FROM "John.Doe";
but that leaves John.Doe with CONNECT privilege, which you will also need to revoke. If you revoke DBA privilege from someone, they retain CONNECT privilege too (and not RESOURCE privilege).
REVOKE CONNECT FROM "John.Doe";
Then you can re-grant the RESOURCE privilege to the user name in lower-case:
GRANT RESOURCE TO "john.doe";
Note that the username must be quoted each time, both to conserve case-sensitivity and because neither john.doe nor John.Doe is a valid identifier because of the . in the middle.
These changes only affect the SysUsers table. Any resources created by John.Doe are still owned by John.Doe and not by john.doe. There is no way to change the ownership of objects. The 'workaround' is to drop and recreate the objects with the correct owner. Beware that dropping an object loses all permissions granted on the object, and also destroys views built on top of the dropped table (or view).
You cannot. Despite the catalog table name, entries in that table represent the Informix database level privileges for that user, not the actual user. It is the GRANT and REVOKE SQL commands that manipulate those entries.
The only way I can think is to REVOKE all database privileges for user John.Doeand GRANT the same privileges to the user john.doe. Note that any object owned by user John.Doe will continue to belong to John.Doe.
Related
I am trying to create a group that has the right to create databases and roles. And then inherit these privileges with the next role. But the error constantly pops up that I don't have rights
Edited: (mistake between 'gg' and 'ggc', but steel doesn't work)
create role ggc with createdb createrole;
create user gg login password 'gg';
grant ggс to gg;
Always get this error: "SQL Error [42501]"
This way is also doesn't work
CREATE ROLE qwe WITH NOLOGIN CREATEDB CREATEROLE;
CREATE ROLE ads WITH LOGIN PASSWORD 'pass';
GRANT qwe TO ads;
SET ROLE ads;
CREATE DATABASE test;
This behavior is normal and is actually documented here:
The role attributes LOGIN, SUPERUSER, CREATEDB, and CREATEROLE can be thought of as special privileges, but they are never inherited as ordinary privileges on database objects are. You must actually SET ROLE to a specific role having one of these attributes in order to make use of the attribute. Continuing the above example, we might choose to grant CREATEDB and CREATEROLE to the admin role. Then a session connecting as role joe would not have these privileges immediately, only after doing SET ROLE admin.
You grant roles to users, not the other way round
I need to create a new firebird-db user which has only access to 4 specific tables. Is there a way to do that?
http://www.destructor.de/firebird/gsec.htm isn't really helpful in that regard.
The - third-party - gsec documentation you link does not provide information about granting rights on tables, because gsec is only for managing users in the security database. In Firebird, rights of users are managed in the individual databases using the GRANT (and REVOKE) statements (it is even possible to grant rights to users that do not exist (yet)). Be aware, Firebird 3 deprecated gsec, and since Firebird 2.5, it is recommended to use the SQL user management statements instead of gsec.
You need to create the user, and then give the user privileges to the tables you want. See the Security chapter in the Firebird 2.5 Language Reference.
A regular, authenticated user has no privileges on any database object
until they are explicitly granted, either to that individual user or
to all users bundled as the user PUBLIC.
Specifically:
Create a user:
create user <username> password '<password>';
See also CREATE USER; to create a user, you need to be either SYSDBA, or you need to have and the admin role in the security database, and the RDB$ADMIN role in the current database, and be logged in specifying the RDB$ADMIN role on connect.
Grant the necessary privileges to the user. For example to give SELECT privileges:
grant select on table <tablename> to user <username>;
To allow select, insert, update and delete:
grant select, insert, update, delete on table <tablename> to user <username>;
See also GRANT; to grant permission to an object, you must be either SYSDBA, the owner of the object, be RDB$ADMIN in the current database, or have been granted the privilege(s) with the WITH GRANT OPTION.
When you need to grant the same set of rights to multiple users, it is better to grant rights to a role, and then grant that role to the users. However in Firebird 3 and earlier, to get the rights granted to a role, the user needs to explicitly specify that role on connect (Firebird 4 will introduce roles that are automatically applied).
I would like to know how the privilege SELECT ANY TABLE works internally in Oracle.
Is it treated as a single privilege? Or is it equivalent to make a GRANT SELECT ON MyTable TO MyUser for each table?
As example, I would like to know if this work :
GRANT SELECT ANY TABLE TO PUBLIC;
REVOKE ALL ON MY_TABLE FROM PUBLIC;
Would I still have access to MY_TABLE from any user after those queries?
Yes, all users would still be able to query MY_TABLE.
You are looking at different privilege types:
The main types of user privileges are as follows:
System privileges—A system privilege gives a user the ability to perform a particular action, or to perform an action on any schema objects of a particular type. For example, the system privilege CREATE TABLE permits a user to create tables in the schema associated with that user, and the system privilege CREATE USER permits a user to create database users.
Object privileges—An objectprivilege gives a user the ability to perform a particular action on a specific schema object. Different object privileges are available for different types of schema objects. The privilege to select rows from the EMPLOYEES table or to delete rows from the DEPARTMENTS table are examples of object privileges.
SELECT ANY TABLE is a system privilege that allows the grantee to:
Query tables, views, or materialized views in any schema except SYS. Obtain row locks using a SELECT ... FOR UPDATE.
When you grant that it is a standalone single privilege, visible in dba_sys_privs. When Oracle decides if the user is allowed to access a table it can look first at system privleges, and only goes on to look for specific object privileges (visible in dba_tab_privs) if there isn't a system privilege that allows the action being performed.
System privileges are not translated into individual privileges on each object in the database - maintaining that would be horrible, as creating a new object would have to automatically figure out who should be granted privileges on it based on the system privilege; and it would mean that you couldn't tell the difference between that and individually granted privileges. So, for instance, if you explicitly granted select privs on a specific table, then the user was granted SELECT ANY TABLE, and then they had SELECT ANY TABLE revoked - what happens to the previous explicit grant?
Your scenario is basically the same, except you've specifed all privileges on the object to be revoked. If those are the only two commands involved then PUBLIC has no explicit privileges on MY_TABLE so revoking doesn't really do anything; but if any explicit privileges on that table had been granted then they would be revoked. That has no impact on the higher-level SELECT ANY TABLE system privileg though.
Privileges are cummulative; revoking a privilege on a specific object doesn't block access to that object, it just removes one possible access route.
Incidentally, hopefully you've used a contrived example, as such powerful system privileges should be granted sparingly and only when really needed. Letting any user query any table in your database potentially blows a big hole in the security model. Again from the docs:
Oracle recommends that you only grant the ANY privileges to trusted users
and
Oracle recommends against granting system privileges to PUBLIC.
and read more in the database security guide.
I'm moving from MySQL to PostgreSQL and have hit a wall with user privileges. I am used to assigning a user all privileges to all tables of a database with the following command:
# MySQL
grant all privileges on mydatabase.* to 'myuser'#'localhost' identified by 'mypassword';
It appears to me that the PostgreSQL 9.x solution involves assigning privileges to a "schema", but the effort required of me to figure out exactly what SQL to issue is proving excessive. I know that a few more hours of research will yield an answer, but I think everyone moving from MySQL to PostgreSQL could benefit from having at least one page on the web that provides a simple and complete recipe. This is the only command I have ever needed to issue for users. I'd rather not have to issue a command for every new table.
I don't know what scenarios have to be handled differently in PostgreSQL, so I'll list some of the scenarios that I have typically had to handle in the past. Assume that we only mean to modify privileges to a single database that has already been created.
(1a) Not all of the tables have been created yet, or (1b) the tables have already been created.
(2a) The user has not yet been created, or (2b) the user has already been created.
(3a) Privileges have not yet been assigned to the user, or (3b) privileges were previously assigned to the user.
(4a) The user only needs to insert, update, select, and delete rows, or (4b) the user also needs to be able to create and delete tables.
I have seen answers that grant all privileges to all databases, but that's not what I want here. Please, I am looking for a simple recipe, although I wouldn't mind an explanation as well.
I don't want to grant rights to all users and all databases, as seems to be the conventional shortcut, because that approach compromises all databases when any one user is compromised. I host multiple database clients and assign each client a different login.
It looks like I also need the USAGE privilege to get the increasing values of a serial column, but I have to grant it on some sort of sequence. My problem got more complex.
Basic concept in Postgres
Roles are global objects that can access all databases in a db cluster - given the required privileges.
A cluster holds many databases, which hold many schemas. Schemas (even with the same name) in different DBs are unrelated. Granting privileges for a schema only applies to this particular schema in the current DB (the current DB at the time of granting).
Every database starts with a schema public by default. That's a convention, and many settings start with it. Other than that, the schema public is just a schema like any other.
Coming from MySQL, you may want to start with a single schema public, effectively ignoring the schema layer completely. I am using dozens of schema per database regularly.
Schemas are a bit (but not completely) like directories in the file system.
Once you make use of multiple schemas, be sure to understand search_path setting:
How does the search_path influence identifier resolution and the "current schema"
Default privileges
Per documentation on GRANT:
PostgreSQL grants default privileges on some types of objects to
PUBLIC. No privileges are granted to PUBLIC by default on tables,
columns, schemas or tablespaces. For other types, the default
privileges granted to PUBLIC are as follows: CONNECT and CREATE TEMP TABLE
for databases; EXECUTE privilege for functions; and USAGE privilege for languages.
All of these defaults can be changed with ALTER DEFAULT PRIVILEGES:
Grant all on a specific schema in the db to a group role in PostgreSQL
Group role
Like #Craig commented, it's best to GRANT privileges to a group role and then make a specific user member of that role (GRANT the group role to the user role). This way it is simpler to deal out and revoke bundles of privileges needed for certain tasks.
A group role is just another role without login. Add a login to transform it into a user role. More:
Why did PostgreSQL merge users and groups into roles?
Predefined roles
Update: Postgres 14 or later adds the new predefined roles (formally "default roles") pg_read_all_data and pg_write_all_data to simplify some of the below. See:
Grant access to all tables of a database
Recipe
Say, we have a new database mydb, a group mygrp, and a user myusr ...
While connected to the database in question as superuser (postgres for instance):
REVOKE ALL ON DATABASE mydb FROM public; -- shut out the general public
GRANT CONNECT ON DATABASE mydb TO mygrp; -- since we revoked from public
GRANT USAGE ON SCHEMA public TO mygrp;
To assign "a user all privileges to all tables" like you wrote (I might be more restrictive):
GRANT ALL ON ALL TABLES IN SCHEMA public TO mygrp;
GRANT ALL ON ALL SEQUENCES IN SCHEMA public TO mygrp; -- don't forget those
To set default privileges for future objects, run for every role that creates objects in this schema:
ALTER DEFAULT PRIVILEGES FOR ROLE myusr IN SCHEMA public
GRANT ALL ON TABLES TO mygrp;
ALTER DEFAULT PRIVILEGES FOR ROLE myusr IN SCHEMA public
GRANT ALL ON SEQUENCES TO mygrp;
-- more roles?
Now, grant the group to the user:
GRANT mygrp TO myusr;
Related answer:
PostgreSQL - DB user should only be allowed to call functions
Alternative (non-standard) setting
Coming from MySQL, and since you want to keep privileges on databases separated, you might like this non-standard setting db_user_namespace. Per documentation:
This parameter enables per-database user names. It is off by default.
Read the manual carefully. I don't use this setting. It does not void the above.
Maybe you could give me an example that grants a specific user
select/insert/update/delete on all tables -- those existing and not
yet created -- of a specific database?
What you call a database in MySQL more closely resembles a PostgreSQL schema than a PostgreSQL database.
Connect to database "test" as a superuser. Here that's
$ psql -U postgres test
Change the default privileges for the existing user "tester".
ALTER DEFAULT PRIVILEGES IN SCHEMA public
GRANT INSERT, SELECT, UPDATE, DELETE ON TABLES
TO tester;
Changing default privileges has no effect on existing tables. That's by design. For existing tables, use standard GRANT and REVOKE syntax.
You can't assign privileges for a user that doesn't exist.
You can forget about the schema if you only use PUBLIC.
Then you do something like this: (see doc here)
GRANT { { SELECT | INSERT | UPDATE | DELETE | TRUNCATE | REFERENCES | TRIGGER }
[, ...] | ALL [ PRIVILEGES ] }
ON { [ TABLE ] table_name [, ...]
| ALL TABLES IN SCHEMA schema_name [, ...] }
TO { [ GROUP ] role_name | PUBLIC } [, ...] [ WITH GRANT OPTION ]
I don't want to grant rights to all users and all databases, as seems to be the conventional shortcut, because that approach compromises all databases when any one user is compromised. I host multiple database clients and assign each client a different login.
OK. When you assign tables to the correct role, the privileges granted will be role-specific and not to all users! Then you can decide who to give roles to.
Create a role for each database. A role can hold many users.
Then assign a client-username to the correct role.
Also assign your-username to each role if needed.
(1a) Not all of the tables have been created yet, or (1b) the tables have already been created.
OK. You can create tables later.
When you are ready, assign tables to the correct client role.
CREATE TABLE tablename();
CREATE ROLE rolename;
ALTER TABLE tablename OWNER TO rolename;
(2a) The user has not yet been created, or (2b) the user has already been created.
OK. Create usernames when you are ready. If your client needs more than one username simply create a second client-username.
CREATE USER username1;
CREATE USER username2;
(3a) Privileges have not yet been assigned to the user, or (3b) privileges were previously assigned to the user.
OK. When you are ready to give privileges, create the user and assign the correct role to her.
Use GRANT-TO command to assign roles to users.
GRANT rolename TO username1;
GRANT rolename TO username2;
(4a) The user only needs to insert, update, select, and delete rows, or (4b) the user also needs to be able to create and delete tables.
OK. You run these commands to add permissions to your users.
GRANT SELECT, UPDATE, INSERT, DELETE ON dbname TO role-or-user-name;
ALTER USER username1 CREATEDB;
I am trying to setup a new role for making the access rights granting easier. I was wondering if there is an easier way to give select on all tables (newly created tables should be accessible automatically) under a schema to selected users. I ran following queries for the same. But still my user is not able to access the specific table.
CREATE ROLE myrole;
GRANT SELECT ON myschema.mytable TO myrole;
GRANT usage ON schema myschema TO myrole;
CREATE USER mytest1 identified BY '***';
GRANT myrole TO mytest1;
After this, when I login with mytest1 user and trying to run select on myschema.mytable it is asking me to grant usage on schema to user. After I grant usage on schema to user directly it is failing with permission denied for that table.
Please help with the same. I am running on vertica 5.0
Update:
I find that u also have to make that role default or explicitely set that role as default for user session for making the role's effect take place.
ALTER USER mytest1 DEFAULT ROLE myrole;
But still, my another question of how to make all tables under a schema accessible to specific users remains.
As per the Vertica SQL Reference Manual.pdf (page 725) (doc version 5.0 - for page numbers)
GRANT (Schema)
...
USAGE
Allows the user access to the objects contained within the
schema. This allows the user to look up objects within the
schema. Note that the user must also be granted access to the
individual objects. See the GRANT TABLE (page 727) ... .
The the user must also be granted access to the individual objects means that you need to also GRANT table.
The two I use is GRANT SELECT and GRANT REFERENCES which allows the user to run queries and join (reference) tables in the query.
Example:
GRANT SELECT ON TABLE [schema].[Table1] TO myUser;
GRANT SELECT ON TABLE [schema].[Table2] TO myUser;
GRANT REFERENCES ON TABLE [schema].[Table1] TO myUser;
GRANT REFERENCES ON TABLE [schema].[Table2] TO myUser;
...
6.0 doc reference GRANT SCHEMA (page 808) and GRANT TABLE (page 813).