Re: alter table schema, default sequences stay the same

Поиск
Список
Период
Сортировка
От Tom Lane
Тема Re: alter table schema, default sequences stay the same
Дата
Msg-id 9547.1277907775@sss.pgh.pa.us
обсуждение исходный текст
Ответ на Re: alter table schema, default sequences stay the same  (Sim Zacks <sim@compulab.co.il>)
Список pgsql-general
Sim Zacks <sim@compulab.co.il> writes:
>> I haven't consumed enough caffeine today to recall the details, but
>> I think you could have ended up with default expressions like the above
>> if the database had been dumped and reloaded from 8.0 or earlier.
>> nextval(regclass) was introduced in 8.1 precisely to solve this type
>> of problem.

> My first database was an 8.0 and at some point we upgraded to 8.2 so
> that must have caused the ?corruption?

Yeah, that would fit.  The upgrade process was intentionally designed to
work that way, because the pre-8.1 behavior of DEFAULT nextval('foo')
was that it always referred to the sequence currently named foo, because
'foo' was just a text constant.  We didn't want to risk breaking things
for anyone who was depending on that behavior.  But now you have to
explicitly put in ::text if that's how you want it to behave ---
otherwise you get a regclass constant, which will track the original
sequence's identity despite renamings.

            regards, tom lane

В списке pgsql-general по дате отправления:

Предыдущее
От: Tim Landscheidt
Дата:
Сообщение: Re: Postgres table contents versioning
Следующее
От: Merlin Moncure
Дата:
Сообщение: Re: Problem with temporary tables