Re: RE: Row Versioning, for jdbc updateable result sets
От | Dave Cramer |
---|---|
Тема | Re: RE: Row Versioning, for jdbc updateable result sets |
Дата | |
Msg-id | 0e6201c0f591$24655e60$0302a8c0@INSPIRON обсуждение исходный текст |
Ответ на | RE: Row Versioning, for jdbc updateable result sets ("Henshall, Stuart - WCP" <SHenshall@westcountrypublications.co.uk>) |
Ответы |
Re: RE: Row Versioning, for jdbc updateable result sets
|
Список | pgsql-hackers |
Stuart, I had no idea that xmin even existed, but having a quick look I think this is what I am looking for. Can I assume that if xmin has changed, then another process has changed the underlying data ? Dave ----- Original Message ----- From: "Henshall, Stuart - WCP" <SHenshall@westcountrypublications.co.uk> To: "'Dave Cramer'" <dave@fastcrypt.com> Cc: <pgsql-hackers@postgresql.org> Sent: Friday, June 15, 2001 5:41 AM Subject: [HACKERS] RE: Row Versioning, for jdbc updateable result sets > Don't know about JDBC, but couldn't you just use UPDATE <xxx> SET > <yyy>=<zzz> WHERE xmin=<stored/old xmin> AND primarykey=<stored/old pk> and > get the number of altered records? (if its zero then you know somethings > wrong and can investigate further) > - Stuart > > > -----Original Message----- > > From: Dave Cramer [SMTP:dave@fastcrypt.com] > > Sent: Thursday, June 14, 2001 4:34 AM > > To: pgsql-hackers@postgresql.org > > Subject: Row Versioning, for jdbc updateable result sets > > > > In order to be able to implement updateable result sets there needs to be > > a mechanism for determining if the underlying data has changed since the > > resultset was fetched. Short of retrieving the current data and comparing > > the entire row, can anyone think of a way possibly using the row version > > to determine if the data has been concurrently changed? > > > > Dave > > ---------------------------(end of broadcast)--------------------------- > TIP 4: Don't 'kill -9' the postmaster > >
В списке pgsql-hackers по дате отправления: