Andreas Joseph Krogh <andreas(at)visena(dot)com> writes:
> Run the attached script and you'll get:
> psql -f error.sql -d test
> psql:error.sql:37: ERROR: attribute number 6 exceeds number of columns 5
Hmm, interesting. IMO, that *should* have thrown an error, but of
course not that one. The ADD COLUMN operations are all processed
in parallel, so it's not okay for one of them to have a GENERATED
expression that refers to another one of the new columns. But you
should have gotten a "no such column" type of error, not a run-time
cross-check failure.
regards, tom lane