steven(dot)winfield(at)cantabcapital(dot)com writes:
> It seems as though pg_blocking_pids() can return a zero-length,
> one-dimensional array whereas users can only create NULL-length,
> zero-dimensional arrays (even though the type suggests it is one
> dimensional: 'integer[]')
This has been fixed recently in HEAD:
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=716ea626a
but we decided not to back-patch the change.
regards, tom lane