Backup log: a lot of DEFAULT "public.id"


#1
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"
[2016-12-29 13:38:14] pg_dump: creating DEFAULT "public.id"

A lot of entries like this in my backup logs. Are they intentional or is there a problem somewhere? Can post whole log, if necessary.