Re: timeout on lock feature
От | Theo Kramer |
---|---|
Тема | Re: timeout on lock feature |
Дата | |
Msg-id | 200104180434.f3I4Ys322280@flame.co.za обсуждение исходный текст |
Ответ на | Re: timeout on lock feature (ncm@zembu.com (Nathan Myers)) |
Список | pgsql-hackers |
> Timeouts are a system-level mechanism that to be useful must refer to > system-level events that are far above anything that PG knows about. > The only way PG could apply reasonable timeouts would be for the > application to dictate them, but the application can better implement > them itself. OK we have the following scenario Session A Session B begin begin insert -- on unique constraint insert -- on same unique constraint -- Session A becomes idle : -- Session B becomes ... or we have (Informix Online) Session A Session B set lock mode to wait [seconds] set lock mode to wait [seconds] begin begin insert -- on unique constraint insert -- on same unique constraint * resource not available error * -- Session B carries on Oracle 7 (OCI) has oopt() call to set wait options for requested resources. Oracle 8 OCI has the same behaviour as PG ie. oopt() is no longer available. I believe that the ability to switch the database to either not wait for resources, or wait a specified period or wait forever (default) is essential especially for interactive applications. Regards Theo
В списке pgsql-hackers по дате отправления: