hot updates and fillfactor

Hi,

I do not understand why hot_updates value is not 0 for pg_database? Given that reloptions is empty for this table that means it has a default value of 100%

Regards,

Fabrice

 SELECT
    relname AS table_name,
    seq_scan AS sequential_scans,
    idx_scan AS index_scans,
    n_tup_ins AS inserts,
    n_tup_upd AS updates,
    n_tup_hot_upd AS hot_updates
FROM
    pg_stat_all_tables
ORDER BY
    hot_updates DESC;


postgres [1728332]=# select t.relname as table_name,
       t.reloptions
from pg_class t
  join pg_namespace n on n.oid = t.relnamespace
where t.relname in ('pg_database')
  and n.nspname = 'pg_catalog';