Re: [HACKERS] MVCC works in serialized mode!

Поиск
Список
Период
Сортировка
От Zeugswetter Andreas IZ5
Тема Re: [HACKERS] MVCC works in serialized mode!
Дата
Msg-id 219F68D65015D011A8E000006F8590C60267B2C3@sdexcsrv1.sd.spardat.at
обсуждение исходный текст
Ответы RE: [HACKERS] MVCC works in serialized mode!  ("Hiroshi Inoue" <Inoue@tpf.co.jp>)
Список pgsql-hackers
>>    Shouldn't we change default transaction mode now?>>    And use option/SET TRANSACTION MODE to switch to>>
un-chainedmode if one like it?>>No comments on this?>I would like to make BEGIN implicit...>Objections?
 
Yes, I object. I think the default behavior should be the one that is sufficient in most cases. 
As to the isolation level: Informix and DB/2 default to read committed mode. In most cases this
is sufficient.Therefore most clients don't need the extra set transaction
isolation statement.
As to transaction blocks: Actually most clients never use commit work, and rememberthat postgresql will never free it's
memorybefore commit. This will
 
hog up memory for otherwise lightweight clients.
I also think that the begin work; commit work; statement block issomewhat part of the postgresql philosophy. We do not
standalonewith this approach (Informix).Actually the other DB's start the transaction with the first
 
modifying statement, in my opinion a rather weird approach. I have seen programs that do a dummy update, just to
simulatea begin work, what a waste.But this alone will not work, because a select statement, that needs
 
a sort would have started the transaction earlier (Since it created
an implicittemp table).I could go on, but you see I don't really like this ...... 
If you want to change the behavior, I think we will need a
changeable default at database level.
Andreas



В списке pgsql-hackers по дате отправления:

Предыдущее
От: Angelos Karageorgiou
Дата:
Сообщение: Re: [HACKERS] psql \d does not work
Следующее
От: Theo Kramer
Дата:
Сообщение: Re: [HACKERS] MVCC works in serialized mode!