Primary key checks not honored when inserting multiple records at once

[amotl]

CrateDB version

5.1.1

CrateDB setup information

docker run -it --rm --publish=4200:4200 --publish=5432:5432 crate:5.1.1 -Cdiscovery.type=single-node -Ccluster.routing.allocation.disk.threshold_enabled=false

Steps to Reproduce

psql postgres://crate@localhost:5432/doc

Running this multiple times does not croak.

CREATE TABLE IF NOT EXISTS testdrive (id INT PRIMARY KEY, data TEXT);
INSERT INTO testdrive VALUES (0, 'zero'), (1, 'one');
INSERT INTO testdrive VALUES (0, 'zero'), (1, 'one');

Expected Result

Would have expected it to croak like this.

CREATE TABLE IF NOT EXISTS testdrive (id INT PRIMARY KEY, data TEXT);
INSERT INTO testdrive VALUES (0, 'zero');
INSERT INTO testdrive VALUES (0, 'zero');

ERROR:  A document with the same primary key exists already

Actual Result

doc=> INSERT INTO testdrive VALUES (0, 'zero'), (1, 'one');
INSERT 0 2
doc=> INSERT INTO testdrive VALUES (0, 'zero'), (1, 'one');
INSERT 0 0

[mfussenegger]

This is expected behavior, the rowcount on the second insert changed from 2 to 0 to indicate that the records weren't inserted.

Also relates to #12218

[amotl]

I see. Thank you!