Re: Using multi-row technique with COPY

[Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>]

Simon Riggs wrote:
> On Tue, 2005-11-29 at 18:51 -0500, Bruce Momjian wrote:
> > Please let me back up and ask a more simplistic question.  I understand
> > the idea of allowing COPY to insert rows with less locking, but I am
> > wondering about the NOLOGGING idea.  On commit, we must guarantee that
> > all the rows are in the table, so what advantage is there to a NOLOGGING
> > option?
> 
> We would need to flush all the blocks in the table out of cache at
> commit time, for that table only. (As with CTAS, CIDX).
> 
> 
> To allow a full discussion, I'll separate the various ideas:
> 1. COPY using bulk copy mode

What is "bulk copy mode"?  Full page loading?

> 2. NOLOGGING

Means flush/fsync table pages on commit.

> 3. Created in this transaction

Reduces locking?

> 4. ERRORTABLES
> 5. Uniqueness violations
> 
> Right now, I think you have reasonable objections/input to (2) that we
> should discuss more before agreeing a way forward. I would aim to do (1)
> first, then return with a full and much better explained proposal for
> (2) for us to discuss, since (2) depends upon (1) somewhat.
> 
> (3) and (4) seem to have been generally accepted, but (5) seems not
> viable with present thinking.

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