外部キーっぽいのに外部キーが張られてないカラムをさがすSQL for PostgreSQL

      SELECT d.nspname, b.relname, h.attname FROM pg_class b
      JOIN pg_namespace d ON b.relnamespace=d.oid
      join pg_attribute h on (b.oid=h.attrelid)
      where b.relkind='r' and h.attname like '%_id'
      and not exists (select true from pg_constraint e
      join pg_class f on (f.oid=e.conrelid) where e.conrelid = b.oid and e.contype='f')      and  h.attnum > 0
      and d.nspname not in ('pg_catalog', 'information_schema');