Re: Least Active Transaction ID function

On Wed, Jul 23, 2014 at 3:53 PM, Rohit Goyal <rhtgyl.87@gmail.com> wrote:
> Hi All,
>
> On Wed, Jul 23, 2014 at 5:01 PM, Rohit Goyal <rhtgyl.87@gmail.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.

> 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.

-- 
Robert Haas
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