Re: Least Active Transaction ID function

Hi Robert,

On Thu, Jul 24, 2014 at 9:32 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Wed, Jul 23, 2014 at 3:53 PM, Rohit Goyal <rhtgyl(dot)87(at)gmail(dot)com> wrote:
> > Hi All,
> >
> > On Wed, Jul 23, 2014 at 5:01 PM, Rohit Goyal <rhtgyl(dot)87(at)gmail(dot)com>
> wrote:
> >>
> >> Hi All,
> >>
> >> I am doing programming with postgresql source code. I want to find out
> the
> >> function which can give me Least active transaction id currenty in the
> >> system.
> >>
> >> Is there any function which can give me that?
> >>
> >> Regards,
> >> Rohit Goyal
> >
> > 1> I know that somewhere there is an active transaction list in
> postgresql.
> > At any point of time, I want to get the smallest transaction present in
> this
> > active tx list or I want to get the transaction id before which all
> > transaction smaller than that are committed/aborted.
> >
> > Is there any function which can give me this value?
>
> See the RecentXmin calculation in GetSnapshotData.
>
> This was really -2 helpful.
1. Can I use this xmin variable directly anytime anywhere in my code as it
is a global variable.
2. What is the difference b/w recentXmin and RecentGlobalXmin. I read the
description but any small detail can clear my mind. :)

Thanks in advance!!

> > 2> I found a function giving GetStableLatestTransactionId(), please tel
> me
> > what this function gives. I was not able to understand the description
> given
> > above it.
>
> I don't know how to help with this; the description seems clear to me.
>
> This is not important now, as you have already told me the variable and
file for recentXmin.:)

Regards,
Rohit

> --
> Robert Haas
> EnterpriseDB: http://www.enterprisedb.com
> The Enterprise PostgreSQL Company
>

--
Regards,
Rohit Goyal