ALTER DATABASE target_database OWNER TO new_onwer;
ALTER DATABASE name OWNER TO new_owner;
ALTER TABLE <tablename> OWNER TO <username>
ALTER TABLE "schemaname"."tablename" OWNER TO role_name;
pg_dump -Fp -f dbbackup.dmp <dbname>
vi dbbackup.dmp
:%s/oldowner/newowner/g
save and exit