Re: simulating row ownership

On Fri, Jan 07, 2005 at 11:52:07AM -0500, Rick Schumeyer wrote:

> I have a table where I want everyone to be able to be able to insert
> and select.

> But they should only be able to update and delete rows that they
> "own".  The table has a column indicating the owner.

> What is the best way to accomplish this?  I'm not real familiar with
> rules, but it seems that I can do this with rules for update and
> delete applied to the table.

Using rules, you could do something like the following:

CREATE TABLE test ( aname TEXT PRIMARY KEY
);

INSERT INTO test ( aname ) VALUES ( 'aaa' );
INSERT INTO test ( aname ) VALUES ( 'yourusername' );

CREATE RULE lock_test_user_update
AS ON UPDATE TO test
WHERE old.aname = CURRENT_USER
DO INSTEAD nothing;

CREATE RULE lock_test_user_delete
AS ON DELETE TO test
WHERE old.aname = CURRENT_USER
DO INSTEAD nothing;

-- 
Ron Peterson
Network & Systems Manager
Mount Holyoke College
http://www.mtholyoke.edu/~rpeterso