Re: Remembering bug #6123

Kevin Grittner <kevin.grittner@wicourts.gov>

From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "Tom Lane" <tgl@sss.pgh.pa.us>
Cc: <pgsql-hackers@postgresql.org>
Date: 2012-01-12T16:16:39Z
Lists: pgsql-hackers
Tom Lane <tgl@sss.pgh.pa.us> wrote:
 
> So what we need to do is check whether the outdate was done by a
> later CommandId than current.  I see that your patch is attempting
> to deal with these issues by testing GetCurrentCommandId(false) !=
> estate->es_output_cid, but that seems completely wrong to me, as
> what it does is complain if *any* additional command has been
> executed in the transaction, regardless of what changed the target
> tuple.  It ought to be comparing the tuple's xmax to
> es_output_cid.  And the comment needs to cover why it's worrying
> about that.
 
OK.  I'll rework based on your comments.
 
> Also, what's the point of testing update_ctid?  I don't see that
> it matters whether the outdate was a delete or an update.
 
The update_ctid code was a carry-over from my old, slightly
different approach, which I failed to change as I should have.  I'll
fix that along with the other.
 
Thanks,
 
-Kevin