Re: POC PATCH: copy from ... exceptions to: (was Re: VLDB Features)

On Thu, Jan 18, 2024 at 6:38 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> Alexander Korotkov <aekorotkov(at)gmail(dot)com> writes:
> > On Wed, Jan 17, 2024 at 9:49 AM Kyotaro Horiguchi
> > <horikyota(dot)ntt(at)gmail(dot)com> wrote:
> >> On the other hand, SAVE_ERROR_TO takes 'error' or 'none', which
> >> indicate "immediately error out" and 'just ignore the failure'
> >> respectively, but these options hardly seem to denote a 'location',
> >> and appear more like an 'action'. I somewhat suspect that this
> >> parameter name intially conceived with the assupmtion that it would
> >> take file names or similar parameters. I'm not sure if others will
> >> agree, but I think the parameter name might not be the best
> >> choice. For instance, considering the addition of the third value
> >> 'log', something like on_error_action (error, ignore, log) would be
> >> more intuitively understandable. What do you think?
>
> > Probably, but I'm not sure about that. The name SAVE_ERROR_TO assumes
> > the next word will be location, not action. With some stretch we can
> > assume 'error' to be location. I think it would be even more stretchy
> > to think that SAVE_ERROR_TO is followed by action.
>
> The other problem with this terminology is that with 'none', what it
> is doing is the exact opposite of "saving" the errors. I agree we
> need a better name.

Agreed.

>
> Kyotaro-san's suggestion isn't bad, though I might shorten it to
> error_action {error|ignore|log} (or perhaps "stop" instead of "error")?
> You will need a separate parameter anyway to specify the destination
> of "log", unless "none" became an illegal table name when I wasn't
> looking. I don't buy that one parameter that has some special values
> while other values could be names will be a good design. Moreover,
> what if we want to support (say) log-to-file along with log-to-table?
> Trying to distinguish a file name from a table name without any other
> context seems impossible.

I've been thinking we can add more values to this option to log errors
not only to the server logs but also to the error table (not sure
details but I imagined an error table is created for each table on
error), without an additional option for the destination name. The
values would be like error_action {error|ignore|save-logs|save-table}.

Regards,

--
Masahiko Sawada
Amazon Web Services: https://aws.amazon.com