connect / as sysdba
create user hajo identified by hajo default tablespace users;
grant connect, resource to hajo;

create role dba_read_role;

grant select on dba_data_files to dba_read_role;
grant select on dba_free_space_coalesced to dba_read_role;
grant select on dba_free_space to dba_read_role;
grant select on dba_tablespaces to dba_read_role;
grant select on dba_tablespace_usage_metrics to dba_read_role;
grant select on dba_temp_files to dba_read_role;
grant select on dba_temp_free_space to dba_read_role;

grant dba_read_role to hajo;

connect hajo/hajo
select * from dba_data_files;
select * from dba_tablespaces;

connect / as sysdba
grant select_catalog_role to dba_read_role;

connect hajo/hajo
select * from v$instance;
select * from v$datafile;

connect / as sysdba
drop role dba_read_role;
drop user hajo cascade;