Re: Re: Proposal: Store "timestamptz" of database creation on "pg_database"

From: Robert Haas <robertmhaas(at)gmail(dot)com>
To: Hannu Krosing <hannu(at)2ndquadrant(dot)com>
Cc: Stephen Frost <sfrost(at)snowman(dot)net>, Andres Freund <andres(at)2ndquadrant(dot)com>, Dimitri Fontaine <dimitri(at)2ndquadrant(dot)fr>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Josh Berkus <josh(at)agliodbs(dot)com>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Re: Proposal: Store "timestamptz" of database creation on "pg_database"
Date: 2013-01-03 14:09:22
Message-ID: CA+TgmoZ0wGe4gpse9fkTWgvD+91T1zbP-jJEoLXhxR=iuV0CNA@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Thu, Jan 3, 2013 at 8:46 AM, Hannu Krosing <hannu(at)2ndquadrant(dot)com> wrote:
> How is "what does database creation date mean?" a different question ?
>
> It is same question as :
>
> what is the creation date of db when I create a replica of my database from
> backup?
>
> does it depend on how I restore my replica ?
>
> can I restore it from pg_dump and still have same creation date ?
>
> etc. etc.

I think you (and Tom) are doing an excellent job of making a simple
problem seem complicated. Suppose a man comes walking out of the
desert looking exhausted and collapses on our front doorstep,
muttering, in a semi-conscious state, the single word "water". Now
this is a somewhat incoherent utterance, so there are several
objections that might be raised:

- It is not clear what the man wants done with the water.
- The amount of water to be provided is unspecified.
- Does he want tap water, bottled water, or club soda?
- Furthermore, if we do give him water, he might go on to ask for a
few crackers and a phone call; we could end up spending the whole
morning on this.
- In a situation of extreme thirst, a solution involving a proper
electrolyte balance would likely be superior to plain water.

Of course, these objections miss the point. Even an imperfect
solution will be better than no solution at all. And it is very
likely that if we simply provide whatever hydrating agent lies closest
to hand, we'll get full marks.

Similarly, in the present situation, I believe that there is little
reason to suppose that the simplest possible implementation of this
feature won't resolve the overwhelming majority of the needs that
people have. We have many features about which users might raise the
same kinds of questions that you are raising about this one, and they
do, and those questions are perfectly valid. But they are not reasons
to remove those features, and the questions you raise are not reasons
to avoid having this one. They are simply things that must be
documented and explained, just as we need to do with every other
feature we ship. And if someone is not perfectly happy with the
design, it won't be the first time for that, either. It does not mean
that it's worse than not having anything.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Peter Eisentraut 2013-01-03 14:12:25 Re: Proposal: Store "timestamptz" of database creation on "pg_database"
Previous Message Ali Dar 2013-01-03 13:49:07 Re: missing rename support