Re: Per-database search_path

Folks,

I'd like to propose a feature for 8.3, which would let login roles
have a default search_path both globally, as it is now, and
per-database. This is because in general no two databases have
any schemas in common, and a login role should be able to do something
reasonable just by connecting.

What would be involved with making this so? So far, I can see:

* Storing this information in pg_catalog somehow
* Setting the search_path when a login role connects

Cheers,
D
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
phone: +1 415 235 3778 AIM: dfetter666
Skype: davidfetter

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DF,

> I'd like to propose a feature for 8.3, which would let login roles
> have a default search_path both globally, as it is now, and
> per-database. This is because in general no two databases have
> any schemas in common, and a login role should be able to do something
> reasonable just by connecting.

Yes. I've been bitten by this more than once ...

However, it almost seems like this would become a piece of the other
per-database-user stuff we'd like to do, like "local superuser".

--
--Josh

Josh Berkus
PostgreSQL @ Sun
San Francisco

On Fri, Sep 29, 2006 at 01:06:09PM -0700, Josh Berkus wrote:
> DF,
>
> > I'd like to propose a feature for 8.3, which would let login roles
> > have a default search_path both globally, as it is now, and
> > per-database. This is because in general no two databases have
> > any schemas in common, and a login role should be able to do
> > something reasonable just by connecting.
>
> Yes. I've been bitten by this more than once ...

Come to think of it, this ties in with the "ON (DIS)CONNECT TRIGGER"
idea that others have brought up in the past. The trigger idea may be
too big a hammer, and might even be ill-advised from a design point of
view, but I thought I'd bring it up anyhow.

> However, it almost seems like this would become a piece of the other
> per-database-user stuff we'd like to do, like "local superuser".

I'm not sure that's the same. The thing about superuser as it exists
now is the ability to write to the filesystem, which means that
there's no boundary really possible. Maybe some kind of tiered system
of users with more than 2 tiers...but that sounds pretty byzantine to
me.

Cheers,
D
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
phone: +1 415 235 3778 AIM: dfetter666
Skype: davidfetter

Remember to vote!

David Fetter <david(at)fetter(dot)org> writes:
> On Fri, Sep 29, 2006 at 01:06:09PM -0700, Josh Berkus wrote:
>> However, it almost seems like this would become a piece of the other
>> per-database-user stuff we'd like to do, like "local superuser".

> I'm not sure that's the same. The thing about superuser as it exists
> now is the ability to write to the filesystem, which means that
> there's no boundary really possible.

Yeah. ISTM the correct generalization is "per-user per-database default
GUC settings", which has nothing to do with superuserness.

regards, tom lane

On Fri, Sep 29, 2006 at 05:41:35PM -0400, Tom Lane wrote:
> David Fetter <david(at)fetter(dot)org> writes:
> > On Fri, Sep 29, 2006 at 01:06:09PM -0700, Josh Berkus wrote:
> >> However, it almost seems like this would become a piece of the
> >> other per-database-user stuff we'd like to do, like "local
> >> superuser".
>
> > I'm not sure that's the same. The thing about superuser as it
> > exists now is the ability to write to the filesystem, which means
> > that there's no boundary really possible.
>
> Yeah. ISTM the correct generalization is "per-user per-database
> default GUC settings", which has nothing to do with superuserness.

This sounds like a TODO for 8.3. What wrinkles might this involve?
Offhand, I'm thinking that it would touch the inheritance stuff that
roles have.

Cheers,
D
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
phone: +1 415 235 3778 AIM: dfetter666
Skype: davidfetter

Remember to vote!

David Fetter <david(at)fetter(dot)org> writes:
> On Fri, Sep 29, 2006 at 05:41:35PM -0400, Tom Lane wrote:
>> Yeah. ISTM the correct generalization is "per-user per-database
>> default GUC settings", which has nothing to do with superuserness.

> This sounds like a TODO for 8.3. What wrinkles might this involve?

Probably rethink the rolconfig/datconfig representation. Maybe it's
time for a separate catalog for the settings.

> Offhand, I'm thinking that it would touch the inheritance stuff that
> roles have.

No, it wouldn't, because defaults only apply at the instant of
connection, so there's no inheritance or SET ROLE to worry about.
Whatever role you log in as is what you get.

regards, tom lane

Added to TODO:

* Allow more complex user/database default GUC settings

Currently, ALTER USER and ALTER DATABASE support per-user and
per-database defaults. Consider adding per-user-and-database
defaults so things like search_path can be defaulted for a
specific user connecting to a specific database.

---------------------------------------------------------------------------

Tom Lane wrote:
> David Fetter <david(at)fetter(dot)org> writes:
> > On Fri, Sep 29, 2006 at 05:41:35PM -0400, Tom Lane wrote:
> >> Yeah. ISTM the correct generalization is "per-user per-database
> >> default GUC settings", which has nothing to do with superuserness.
>
> > This sounds like a TODO for 8.3. What wrinkles might this involve?
>
> Probably rethink the rolconfig/datconfig representation. Maybe it's
> time for a separate catalog for the settings.
>
> > Offhand, I'm thinking that it would touch the inheritance stuff that
> > roles have.
>
> No, it wouldn't, because defaults only apply at the instant of
> connection, so there's no inheritance or SET ROLE to worry about.
> Whatever role you log in as is what you get.
>
> regards, tom lane
>
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend

--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +

On Fri, Sep 29, 2006 at 11:55:18PM -0400, Bruce Momjian wrote:
>
> Added to TODO:
>
> * Allow more complex user/database default GUC settings
>
> Currently, ALTER USER and ALTER DATABASE support per-user and
> per-database defaults. Consider adding per-user-and-database
> defaults so things like search_path can be defaulted for a
> specific user connecting to a specific database.

Is anybody claiming this TODO? Is the design fleshed out enough for
someone to go forward with it?

Cheers,
D

>
> ---------------------------------------------------------------------------
>
> Tom Lane wrote:
> > David Fetter <david(at)fetter(dot)org> writes:
> > > On Fri, Sep 29, 2006 at 05:41:35PM -0400, Tom Lane wrote:
> > >> Yeah. ISTM the correct generalization is "per-user per-database
> > >> default GUC settings", which has nothing to do with superuserness.
> >
> > > This sounds like a TODO for 8.3. What wrinkles might this involve?
> >
> > Probably rethink the rolconfig/datconfig representation. Maybe it's
> > time for a separate catalog for the settings.
> >
> > > Offhand, I'm thinking that it would touch the inheritance stuff that
> > > roles have.
> >
> > No, it wouldn't, because defaults only apply at the instant of
> > connection, so there's no inheritance or SET ROLE to worry about.
> > Whatever role you log in as is what you get.
> >
> > regards, tom lane
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 6: explain analyze is your friend
>
> --
> Bruce Momjian bruce(at)momjian(dot)us
> EnterpriseDB http://www.enterprisedb.com
>
> + If your life is a hard drive, Christ can be your backup. +

--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
phone: +1 415 235 3778 AIM: dfetter666
Skype: davidfetter

Remember to vote!

David Fetter wrote:
> On Fri, Sep 29, 2006 at 11:55:18PM -0400, Bruce Momjian wrote:
> >
> > Added to TODO:
> >
> > * Allow more complex user/database default GUC settings
> >
> > Currently, ALTER USER and ALTER DATABASE support per-user and
> > per-database defaults. Consider adding per-user-and-database
> > defaults so things like search_path can be defaulted for a
> > specific user connecting to a specific database.
>
> Is anybody claiming this TODO? Is the design fleshed out enough for
> someone to go forward with it?

I think we just need to decide on the user API for this.

---------------------------------------------------------------------------

>
> Cheers,
> D
>
> >
> > ---------------------------------------------------------------------------
> >
> > Tom Lane wrote:
> > > David Fetter <david(at)fetter(dot)org> writes:
> > > > On Fri, Sep 29, 2006 at 05:41:35PM -0400, Tom Lane wrote:
> > > >> Yeah. ISTM the correct generalization is "per-user per-database
> > > >> default GUC settings", which has nothing to do with superuserness.
> > >
> > > > This sounds like a TODO for 8.3. What wrinkles might this involve?
> > >
> > > Probably rethink the rolconfig/datconfig representation. Maybe it's
> > > time for a separate catalog for the settings.
> > >
> > > > Offhand, I'm thinking that it would touch the inheritance stuff that
> > > > roles have.
> > >
> > > No, it wouldn't, because defaults only apply at the instant of
> > > connection, so there's no inheritance or SET ROLE to worry about.
> > > Whatever role you log in as is what you get.
> > >
> > > regards, tom lane
> > >
> > > ---------------------------(end of broadcast)---------------------------
> > > TIP 6: explain analyze is your friend
> >
> > --
> > Bruce Momjian bruce(at)momjian(dot)us
> > EnterpriseDB http://www.enterprisedb.com
> >
> > + If your life is a hard drive, Christ can be your backup. +
>
> --
> David Fetter <david(at)fetter(dot)org> http://fetter.org/
> phone: +1 415 235 3778 AIM: dfetter666
> Skype: davidfetter
>
> Remember to vote!

--
Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

+ If your life is a hard drive, Christ can be your backup. +

Bruce Momjian <bruce(at)momjian(dot)us> writes:
> David Fetter wrote:
>> Is anybody claiming this TODO? Is the design fleshed out enough for
>> someone to go forward with it?

> I think we just need to decide on the user API for this.

... and the catalog representation.

regards, tom lane