Re: BUG #17511: Inconsistent permissions on some information_schema tables

On Mon, Jun 6, 2022 at 11:50 AM PG Bug reporting form <
noreply@postgresql.org> wrote:

> The following bug has been logged on the website:
>
> Bug reference:      17511
> Logged by:          Kirk Parker
> Email address:      khp@equatoria.us
> PostgreSQL version: 13.7
> Operating system:   AWS Linux 2 -- 4.14.276-211.499.amzn2.x86_64
> Description:
> [...]
> The table at issue is constraint_column_usage--the ordinary role 'apache'
> does not have SELECT rights to that table, though it does to the other two
> catalog tables used by this query.
>
> Yes, there's an easy workaround by just GRANTing SELECT on that table to
> 'apache', but it seems like an odd inconsistency. Interestingly, the same
> limitation does not apply to pg_catalog.pg_get_constraintdef(), which is
> used by psql's \dt command, but that query does not produce the local
> column
> name as a separate result column (which is more useful for my immediate
> purpose here.)
>

Haven't tried to duplicate but I'm not following.

information_schema provides a view of the database that is filtered by user
permissions.  pg_catalog does not take into consideration permissions.
This would be on the contents.  All users can select from either without
getting a permission denied error.

David J.