Re: Change COPY ... ON_ERROR ignore to ON_ERROR ignore_row

On Fri, Jan 26, 2024 at 11:09 PM David G. Johnston
<david(dot)g(dot)johnston(at)gmail(dot)com> 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.