Tablespace Utilization Script in Oracle

How to check oracle tablespace report 
1. Check the database details.
2. Check the tablespace Utilization.
3. Check the details of the datafiles for a particular TableSpace which needs attention.
4. Resize or Add the datafiles as per the standards of the existing datafiles on the database.

1. Check the database details.
$ sqlplus "/as sysdba"

set pages 9999 lines 300
col OPEN_MODE for a10
col HOST_NAME for a30
select name DB_NAME,HOST_NAME,DATABASE_ROLE from v$database,v$instance;

2. Check the tablespace Utilization.
Tablespace Utilization Script including AUTOEXTEND (IN GB)
----------------------------------------------------------
$ sqlplus "/as sysdba"

set pages 50000 lines 32767
col tablespace_name format a30
col TABLESPACE_NAME heading "Tablespace|Name"
col Allocated_size heading "Allocated|Size(GB)" form 99999999.99
col Current_size heading "Current|Size(GB)" form 99999999.99
col Used_size heading "Used|Size(GB)" form 99999999.99
col Available_size heading "Available|Size(GB)" form 99999999.99
col Pct_used heading "%Used (vs)|(Allocated)" form 99999999.99

select a.tablespace_name
        ,a.alloc_size/1024/1024/1024 Allocated_size
        ,a.cur_size/1024/1024/1024 Current_Size
        ,(u.used+a.file_count*65536)/1024/1024/1024 Used_size
        ,(a.alloc_size-(u.used+a.file_count*65536))/1024/1024/1024 Available_size
        ,((u.used+a.file_count*65536)*100)/a.alloc_size Pct_used
from     dba_tablespaces t
        ,(select t1.tablespace_name
        ,nvl(sum(s.bytes),0) used
        from  dba_segments s
        ,dba_tablespaces t1
         where t1.tablespace_name=s.tablespace_name(+)
         group by t1.tablespace_name) u
        ,(select d.tablespace_name
        ,sum(greatest(d.bytes,nvl(d.maxbytes,0))) alloc_size
        ,sum(d.bytes) cur_size
        ,count(*) file_count
        from dba_data_files d
        group by d.tablespace_name) a
where t.tablespace_name=u.tablespace_name
and t.tablespace_name=a.tablespace_name
order by t.tablespace_name
/

Tablespace Utilization Script (including AUTOEXTEND) for generating report of more than 80 % used tablespaces (IN GB)
---------------------------------------------------------------------------------------------------------------------
set pages 50000 lines 32767
col tablespace_name format a30
col TABLESPACE_NAME heading "Tablespace|Name"
col Allocated_size heading "Allocated|Size(GB)" form 99999999.99
col Current_size heading "Current|Size(GB)" form 99999999.99
col Used_size heading "Used|Size(GB)" form 99999999.99
col Available_size heading "Available|Size(GB)" form 99999999.99
col Pct_used heading "%Used (vs)|(Allocated)" form 99999999.99

select a.tablespace_name
        ,a.alloc_size/1024/1024/1024 Allocated_size
        ,a.cur_size/1024/1024/1024 Current_Size
        ,(u.used+a.file_count*65536)/1024/1024/1024 Used_size
        ,(a.alloc_size-(u.used+a.file_count*65536))/1024/1024/1024 Available_size
        ,((u.used+a.file_count*65536)*100)/a.alloc_size Pct_used
from     dba_tablespaces t
        ,(select t1.tablespace_name
        ,nvl(sum(s.bytes),0) used
        from  dba_segments s
        ,dba_tablespaces t1
         where t1.tablespace_name=s.tablespace_name(+)
         group by t1.tablespace_name) u
        ,(select d.tablespace_name
        ,sum(greatest(d.bytes,nvl(d.maxbytes,0))) alloc_size
        ,sum(d.bytes) cur_size
        ,count(*) file_count
        from dba_data_files d
        group by d.tablespace_name) a
where t.tablespace_name=u.tablespace_name
and ((u.used+a.file_count*65536)*100)/a.alloc_size>80
and t.tablespace_name=a.tablespace_name
order by t.tablespace_name
/

3. Check the details of the datafiles for a particular TableSpace which needs attention.
Datafiles of a particular TableSpace:
------------------------------------
set pages 50000 lines 32767
col tablespace_name for a30
col CREATION_TIME for a15
col file_name for a70
select dd.tablespace_name TABLESPACE_NAME,dd.file_name,dd.bytes/1024/1024 Size_MB,dd.autoextensible,dd.maxbytes/1024/1024 MAXSIZE_MB,df.CREATION_TIME
from dba_data_files dd, v$datafile df where df.name=dd.file_name and tablespace_name='&TABLESPACENAME' order by 1,2,6;

Note:- If required, can get the DDL of a tablespace as below.

TABLESPACE DDL
--------------
set pagesize 0
SET LONG 9999999
select dbms_metadata.get_ddl('TABLESPACE','&TABLESPACE_NAME') FROM DUAL;