Обсуждение: Granting permission on a sequence to a group

Hi,

I have a sequence seq_page owned by user vrnsys. Vrnsys has granted "select" on seq_page to group vrn_admin. vrn_admin group has had user vrngui added to it, but vrngui is not able to access the sequence (permission denied for sequence seq_page).

1. Any ideas why this isn't working?

Thanks in advance,

Jed S. Walker

On Thu, Apr 21, 2005 at 03:50:04PM -0600, Walker, Jed S wrote:
>
> I have a sequence seq_page owned by user vrnsys. Vrnsys has granted "select"
> on seq_page to group vrn_admin. vrn_admin group has had user vrngui added to
> it, but vrngui is not able to access the sequence (permission denied for
> sequence seq_page).

vrngui is probably trying to execute nextval('seq_page').  SELECT
privilege on a sequence allows currval(), but nextval() requires
UPDATE privilege.  Try this:

  GRANT SELECT, UPDATE ON seq_page TO GROUP vrn_admin;

For more information, see the documentation for GRANT:

http://www.postgresql.org/docs/8.0/interactive/sql-grant.html

--
Michael Fuhr
http://www.fuhr.org/~mfuhr/

I found a note in a book that states that using "nextval" can't be done with only select privileges, but it doesn't say what else is needed. Can someone tell me (hopefully I find it eventually)?

_____________________________________________
From:   Walker, Jed S 
Sent:   Thursday, April 21, 2005 3:50 PM
To:     'pgsql-novice@postgresql.org'
Subject:        Granting permission on a sequence to a group

Hi,

I have a sequence seq_page owned by user vrnsys. Vrnsys has granted "select" on seq_page to group vrn_admin. vrn_admin group has had user vrngui added to it, but vrngui is not able to access the sequence (permission denied for sequence seq_page).

1. Any ideas why this isn't working?

Thanks in advance,

Jed S. Walker

OK, I think I figured this out, but if someone can confirm that this is the correct way to do this I'd appreciate it.

Since a sequence in postgres is actually a table, I realized that to pull a value off and have it increment you must be able to update the table. So I granted select and update on the sequence to the group, and now the user's in the group are able to use nextval().

Is this definitely the correct way to handle this?

The thing I really don't like about this is that now the user's in that group can perform setval() on the sequence! That's seem like a big risk.

If someone can confirm my solution or give me the proper way to do this I would greatly appreciate it.

Thanks again,

Jed.

_____________________________________________
From:   Walker, Jed S 
Sent:   Friday, April 22, 2005 8:21 AM
To:     Walker, Jed S; 'pgsql-novice@postgresql.org'
Subject:        RE: Granting permission on a sequence to a group

I found a note in a book that states that using "nextval" can't be done with only select privileges, but it doesn't say what else is needed. Can someone tell me (hopefully I find it eventually)?

_____________________________________________
From:   Walker, Jed S 
Sent:   Thursday, April 21, 2005 3:50 PM
To:     'pgsql-novice@postgresql.org'
Subject:        Granting permission on a sequence to a group

Hi,

I have a sequence seq_page owned by user vrnsys. Vrnsys has granted "select" on seq_page to group vrn_admin. vrn_admin group has had user vrngui added to it, but vrngui is not able to access the sequence (permission denied for sequence seq_page).

1. Any ideas why this isn't working?

Thanks in advance,

Jed S. Walker

On Fri, Apr 22, 2005 at 08:29:35 -0600,
  "Walker, Jed S" <Jed_Walker@cable.comcast.com> wrote:
> correct way to do this I'd appreciate it.
>
> Since a sequence in postgres is actually a table, I realized that to pull a
> value off and have it increment you must be able to update the table. So I
> granted select and update on the sequence to the group, and now the user's
> in the group are able to use nextval().
>
> Is this definitely the correct way to handle this?
>
> The thing I really don't like about this is that now the user's in that
> group can perform setval() on the sequence! That's seem like a big risk.
>
> If someone can confirm my solution or give me the proper way to do this I
> would greatly appreciate it.

This has been discussed in the past. My memory is that people were amenable
to using INSERT to give access to nextval and UPDATE to give access to
setval. But I don't think anyone volunteered to do this.

----- Original Message -----

From: Walker, Jed S

To: 'pgsql-novice@postgresql.org'

Sent: Friday, April 22, 2005 4:29 PM

Subject: Re: [NOVICE] Granting permission on a sequence to a group

OK, I think I figured this out, but if someone can confirm that this is the correct way to do this I'd appreciate it.

Since a sequence in postgres is actually a table, I realized that to pull a value off and have it increment you must be able to update the table. So I granted select and update on the sequence to the group, and now the user's in the group are able to use nextval().

Is this definitely the correct way to handle this?

The thing I really don't like about this is that now the user's in that group can perform setval() on the sequence! That's seem like a big risk.

If someone can confirm my solution or give me the proper way to do this I would greatly appreciate it.

Thanks again,

Jed.

_____________________________________________
From:   Walker, Jed S 
Sent:   Friday, April 22, 2005 8:21 AM
To:     Walker, Jed S; 'pgsql-novice@postgresql.org'
Subject:        RE: Granting permission on a sequence to a group

I found a note in a book that states that using "nextval" can't be done with only select privileges, but it doesn't say what else is needed. Can someone tell me (hopefully I find it eventually)?

_____________________________________________
From:   Walker, Jed S 
Sent:   Thursday, April 21, 2005 3:50 PM
To:     'pgsql-novice@postgresql.org'
Subject:        Granting permission on a sequence to a group

Hi,

I have a sequence seq_page owned by user vrnsys. Vrnsys has granted "select" on seq_page to group vrn_admin. vrn_admin group has had user vrngui added to it, but vrngui is not able to access the sequence (permission denied for sequence seq_page).

1. Any ideas why this isn't working?

Thanks in advance,

Jed S. Walker

That seems like a good way to handle it. Thanks for the info!

-----Original Message-----
From: Bruno Wolff III [mailto:bruno@wolff.to]
Sent: Friday, April 22, 2005 9:14 AM
To: Walker, Jed S
Cc: 'pgsql-novice@postgresql.org'
Subject: Re: Granting permission on a sequence to a group

On Fri, Apr 22, 2005 at 08:29:35 -0600,
  "Walker, Jed S" <Jed_Walker@cable.comcast.com> wrote:
> correct way to do this I'd appreciate it.
>
> Since a sequence in postgres is actually a table, I realized that to
> pull a value off and have it increment you must be able to update the
> table. So I granted select and update on the sequence to the group,
> and now the user's in the group are able to use nextval().
>
> Is this definitely the correct way to handle this?
>
> The thing I really don't like about this is that now the user's in
> that group can perform setval() on the sequence! That's seem like a big
risk.
>
> If someone can confirm my solution or give me the proper way to do
> this I would greatly appreciate it.

This has been discussed in the past. My memory is that people were amenable
to using INSERT to give access to nextval and UPDATE to give access to
setval. But I don't think anyone volunteered to do this.