Re: Changing behavior of BEGIN...sleep...do something...COMMIT - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Changing behavior of BEGIN...sleep...do something...COMMIT
Date
Msg-id 200303291656.h2TGu7k20680@candle.pha.pa.us
Whole thread Raw
In response to Re: Changing behavior of BEGIN...sleep...do something...COMMIT  (Alvaro Herrera <alvherre@dcc.uchile.cl>)
Responses Re: Changing behavior of BEGIN...sleep...do something...COMMIT
List pgsql-hackers
Alvaro Herrera wrote:
> On Fri, Mar 28, 2003 at 11:13:28PM -0500, Tom Lane wrote:
> 
> > The other thing that could be thought about here is when to freeze the
> > value of now().  Currently now() is frozen when BEGIN is received.
> > We could keep doing that, but it seems to me it would make more sense
> > to freeze now() when the transaction snapshot is established.  In a
> > very real sense, the transaction snapshot defines "when the transaction
> > starts" --- so shouldn't now() agree?
> 
> Yes, I saw this in the code and wondered about the inconsistency.  I
> agree the timestamp should be taken at the same time as the snapshot.
> 
> While at this, what do you think about adding the necessary variables
> to make now('transaction') and now('query') possible?

TODO already has:
* Add now("transaction|statement|clock") functionality

--  Bruce Momjian                        |  http://candle.pha.pa.us pgman@candle.pha.pa.us               |  (610)
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