Re: Small fix on COPY ON_ERROR document

On Mon, 29 Jan 2024 15:47:25 +0900
Yugo NAGATA <nagata(at)sraoss(dot)co(dot)jp> wrote:

> On Sun, 28 Jan 2024 19:14:58 -0700
> "David G. Johnston" <david(dot)g(dot)johnston(at)gmail(dot)com> wrote:
>
> > > Also, I think "invalid input syntax" is a bit ambiguous. For example,
> > > COPY FROM raises an error when the number of input column does not match
> > > to the table schema, but this error is not ignored by ON_ERROR while
> > > this seems to fall into the category of "invalid input syntax".
> >
> >
> >
> > It is literally the error text that appears if one were not to ignore it.
> > It isn’t a category of errors. But I’m open to ideas here. But being
> > explicit with what on actually sees in the system seemed preferable to
> > inventing new classification terms not otherwise used.
>
> Thank you for explanation! I understood the words was from the error messages
> that users actually see. However, as Torikoshi-san said in [1], errors other
> than valid input syntax (e.g. range error) can be also ignored, therefore it
> would be better to describe to be ignored errors more specifically.
>
> [1] https://www.postgresql.org/message-id/7f1457497fa3bf9dfe486f162d1c8ec6%40oss.nttdata.com
>
> >
> > >
> > > So, keeping consistency with the existing description, we can say:
> > >
> > > "Specifies which how to behave when encountering an error due to
> > > column values unacceptable to the input function of each attribute's
> > > data type."
> >
> >
> > Yeah, I was considering something along those lines as an option as well.
> > But I’d rather add that wording to the glossary.
>
> Although I am still be not convinced if we have to introduce the words
> "soft error" to the documentation, I don't care it if there are no other
> opposite opinions.

Attached is a updated patch v3, which is a version that uses the above
wording instead of "soft error".

> >
> > > Currently, ON_ERROR doesn't support other soft errors, so it can explain
> > > it more simply without introducing the new concept, "soft error" to users.
> > >
> > >
> > Good point. Seems we should define what user-facing errors are ignored
> > anywhere in the system and if we aren’t consistently leveraging these in
> > all areas/commands make the necessary qualifications in those specific
> > places.
> >
>
> > > I think "left in a deleted state" is also unclear for users because this
> > > explains the internal state but not how looks from user's view.How about
> > > leaving the explanation "These rows will not be visible or accessible" in
> > > the existing statement?
> > >
> >
> > Just visible then, I don’t like an “or” there and as tuples at least they
> > are accessible to the system, in vacuum especially. But I expected the
> > user to understand “as if you deleted it” as their operational concept more
> > readily than visible. I think this will be read by people who haven’t read
> > MVCC to fully understand what visible means but know enough to run vacuum
> > to clean up updated and deleted data as a rule.
>
> Ok, I agree we can omit "or accessible". How do you like the followings?
> Still redundant?
>
> "If the command fails, these rows are left in a deleted state;
> these rows will not be visible, but they still occupy disk space. "

Also, the above statement is used in the patch.

Regards,
Yugo Nagata

> Regards,
> Yugo Nagata
>
> --
> Yugo NAGATA <nagata(at)sraoss(dot)co(dot)jp>
>
>

--
Yugo NAGATA <nagata(at)sraoss(dot)co(dot)jp>