Hello,
assume the following table:
create table test
(
id integer not null generated always as identity,
data integer not null
);
The following insert works fine:
insert into test (id, data)
values (default,1);
However, a multi-row insert like the following:
insert into test (id, data)
values
(default,1),
(default,2);
fails with:
ERROR: cannot insert into column "id"
Detail: Column "id" is an identity column defined as GENERATED ALWAYS.
Hint: Use OVERRIDING SYSTEM VALUE to override.
My question is:
* If DEFAULT is not allowed for identity columns, then why does the single-row insert work?
* If DEFAULT _is_ allowed, then why does the multi-row insert fail?
The above happens with Postgres 10,11 and 12
Regards
Thomas