SERIALIZABLE and INSERTs with multiple VALUES

[Jason Dusek <jason.dusek@xxxxxxxxx>]

Hi All,

I notice the following oddity:

 =# CREATE TABLE with_pk (i integer PRIMARY KEY);
CREATE TABLE

 =# BEGIN;
BEGIN
 =# INSERT INTO with_pk VALUES (1) ON CONFLICT DO NOTHING;
INSERT 0 1
 =# INSERT INTO with_pk VALUES (1) ON CONFLICT DO NOTHING;
INSERT 0 0
 =# END;
COMMIT

 =# BEGIN;
BEGIN
 =# INSERT INTO with_pk VALUES (2), (2) ON CONFLICT DO NOTHING;
ERROR:  could not serialize access due to concurrent update
 =# END;
ROLLBACK

How are these two transactions different?

Kind Regards,

  Jason Dusek

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