Обсуждение: Re: [ADMIN] Latest transcation

Consider this:
Transcation begin
'
'
    Insert on table x
'
'
Trascation end;

My client C++ front end is multi-threaded. The above 'transcation' block
is in thread -y .
I want to know the info. abt' last row inserted into table in this
transcation block.
Info contains the details like time of insertion of a row and data in
that row.

I think this sufficely explains what I want.

-Anagha
-----Original Message-----
From: Bruno Wolff III [mailto:bruno@wolff.to]
Sent: Thursday, June 19, 2003 4:00 PM
To: Anagha Joshi
Cc: pgsql-admin@postgresql.org
Subject: Re: [ADMIN] Latest transcation


On Thu, Jun 19, 2003 at 10:46:22 +0530,
  Anagha Joshi <ajoshi@nulinkinc.com> wrote:
> Hi All,
> Is there any way to know programatically which is the latest
> insert/update occured to a particular table? What are the values which

> are inserted/updated to that table?

That depends on what you really are trying to do. It sounds like using a
sequnce, nextval and currval might work. That could be used to track the
latest change in one session.

If you try to look at the latest change to a table accross all sessions,
things get a bit murky.

A more precise description of what you are trying to do might result in
some other suggestions.

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On Thursday 19 June 2003 04:41, Anagha Joshi wrote:
> My client C++ front end is multi-threaded. The above 'transcation' block
> is in thread -y .
> I want to know the info. abt' last row inserted into table in this
> transcation block.
> Info contains the details like time of insertion of a row and data in
> that row.
>
> I think this sufficely explains what I want.
>

There are some things you can do at the application level to record what was
done in a seperate thread or even process. With threads, you can use shared
variables and semaphores. With processes, you can use some form of IPC or
shared memory.

If you decide to go at an application layer, it is beyond the scope of the
ADMIN list, and better suited for a discussion with your peers in that
language and environment.

If you go for a server-side solution (because the application doesn't know
what was last inserted and when), then you'll want to use triggers as I
described in a previous posting.

- --
Jonathan Gardner <jgardner@jonathangardner.net>
(was jgardn@alumni.washington.edu)
Live Free, Use Linux!
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