Re: [SQL] CURRENT_TIMESTAMP

Поиск
Список
Период
Сортировка
От Manfred Koizar
Тема Re: [SQL] CURRENT_TIMESTAMP
Дата
Msg-id sb70pugqu6ifglqe9lv886u3sna328g0ks@4ax.com
обсуждение исходный текст
Ответ на Re: [SQL] CURRENT_TIMESTAMP  (Martijn van Oosterhout <kleptog@svana.org>)
Список pgsql-general
On Tue, 24 Sep 2002 11:19:12 +1000, Martijn van Oosterhout
<kleptog@svana.org> wrote:
>Well, what I would suggest is that when you wrap several statements into a
>single transaction with begin/commit, the whole lot could be considered a
>single statement (since they form an atomic transaction so in a sense they
>are all executed simultaneously).

The people who wrote the specification knew about transactions.  If
they had wanted what you describe above, they would have written:

  3) If a transaction generally contains more than one reference
     to one or more <datetime value function>s, then all such ref-
     erences are effectively evaluated simultaneously. The time of
     evaluation of the <datetime value function> during the execution
     of the transaction is implementation-dependent.

But they wrote "SQL-statement", not "transaction".

>And hence Postgresql is perfectly compliant.

I'm not so sure.

>The current definition is, I would say, the most useful definition. Can you
>give an example where your definition would be more useful?

I did not write the standard, I'm only reading it.  I have no problem
with an implementation that deviates from the standard "because we
know better".  But we should users warn about this fact and not tell
them it is compliant.

Servus
 Manfred

В списке pgsql-general по дате отправления:

Предыдущее
От: "Andrew Bartley"
Дата:
Сообщение: pg_attribute
Следующее
От: Martijn van Oosterhout
Дата:
Сообщение: Re: State of Replication?