revoked permissions on table still allows users to see table's structure

Hi All

I'm new to the list, but have a few years as postgres user. I want to
share what I consider a rare behavior of postgresql regarding database
object's premissions:

I have noticed that there is no way (at least no one I know) to prevent
a user from seeing the table's structures in a database.

I created a new user (user1) and do the following:

'revoke all on all tables in schema public from public;'

After that, user1 cant do select, inserts , etc from database's tables.
But still is able to see my table's structure:

voicemax=>select * from tasks;
ERROR:  permission denied for relation tasks
voicemax=> delete from tasks where task_id=6;
ERROR:  permission denied for relation tasks
voicemax=> \d tasks
                                         Table "public.tasks"
      Column      |          Type          |
Modifiers
-----------------+------------------------+---------------------------------------------------------
  task_id         | bigint                 | not null
  task_name       | character varying(32)  | not null
  description     | character varying(128) |
  enabled         | integer                | default 0
Indexes:
     "tasks_task_name_key" UNIQUE, btree (task_name)

The same behavior occurs when this user is logged from pgAdmin. User can
see all table's structure, even if have no privileges on database tables.

Is this a normal behavior of the product ?
Is there a way to prevent a user from seeing my table's, procedure's and
function's code ?

Thanks in advance.

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Juan R. Cuervo Soto
Quality Telecom Ltd
www.quality-telecom.net
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