public inbox for [email protected]  

help / color / mirror / Atom feed

From: jian he <[email protected]>
To: David G. Johnston <[email protected]>
Cc: PostgreSQL Hackers <[email protected]>
Subject: Re: Change COPY ... ON_ERROR ignore to ON_ERROR ignore_row
Date: Mon, 29 Jan 2024 07:50:00 +0800
Message-ID: <CACJufxExhY9P8a-rk21wR2NXF-UydMjictyiKiMMi_Z4iX6gNQ@mail.gmail.com> (raw)
In-Reply-To: <CAKFQuwawy1e6YR4S=j+y7pXqg_Dw1WBVrgvf=BP3d1_aSfe_+Q@mail.gmail.com>
References: <CAKFQuwawy1e6YR4S=j+y7pXqg_Dw1WBVrgvf=BP3d1_aSfe_+Q@mail.gmail.com>

On Fri, Jan 26, 2024 at 11:09 PM David G. Johnston
<[email protected]> wrote:
>
> Hi,
>
> The option choice of "ignore" in the COPY ON_ERROR clause seems overly generic.  There would seem to be two relevant ways to ignore bad column input data - drop the entire row or just set the column value to null.  I can see us wanting to provide the set to null option and in any case having the option name be explicit that it ignores the row seems like a good idea.

two issue I found out while playing around with it;
create table x1(a int not null, b int not null );

you can only do:
COPY x1 from stdin (on_error 'null');
but you cannot do
COPY x1 from stdin (on_error null);
we need to hack the gram.y to escape the "null". I don't know how to
make it work.
related post I found:
https://stackoverflow.com/questions/31786611/how-to-escape-flex-keyword

another issue:
COPY x1 from stdin (on_error null);

when we already have `not null` top level constraint for table x1.
Do we need an error immediately?
"on_error null" seems to conflict with `not null` constraint (assume
refers to the same column).
it may fail while doing bulk inserts while on_error is set to null
because of violating a not null constraint.

view thread (20+ messages)  latest in thread

reply

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Reply to all the recipients using the --to and --cc options:
  reply via email

  To: [email protected]
  Cc: [email protected], [email protected], [email protected]
  Subject: Re: Change COPY ... ON_ERROR ignore to ON_ERROR ignore_row
  In-Reply-To: <CACJufxExhY9P8a-rk21wR2NXF-UydMjictyiKiMMi_Z4iX6gNQ@mail.gmail.com>

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox