How to Add a Datafile in Oracle Database

To Check Database
-----------------

sqlplus "/as sysdba"
set pages 9999 lines 300
col OPEN_MODE for a10
col HOST_NAME for a10
select name DB_NAME,INSTANCE_NAME,HOST_NAME,OPEN_MODE,version DB_VERSION,DATABASE_STATUS,DATABASE_ROLE,PROTECTION_LEVEL,CONTROLFILE_TYPE,LOGINS,to_char(STARTUP_TIME,'DD-MON-YYYY HH24:MI:SS') "UP TIME"from v$database,gv$instance;

ASM Space Report
----------------

SET LINESIZE 150
SET PAGESIZE 9999
SET VERIFY off
COLUMN group_name             FORMAT a20           HEAD 'Disk Group|Name'
COLUMN sector_size            FORMAT 99,999        HEAD 'Sector|Size'
COLUMN block_size             FORMAT 99,999        HEAD 'Block|Size'
COLUMN allocation_unit_size   FORMAT 999,999,999   HEAD 'Allocation|Unit Size'
COLUMN state                  FORMAT a11           HEAD 'State'
COLUMN type                   FORMAT a6            HEAD 'Type'
COLUMN total_mb               FORMAT 999,999,999   HEAD 'Total Size (MB)'
COLUMN used_mb                FORMAT 999,999,999   HEAD 'Used Size (MB)'
COLUMN pct_used               FORMAT 999.99        HEAD 'Pct. Used'

SELECT
    distinct name                            group_name
  , sector_size                              sector_size
  , block_size                               block_size
  , allocation_unit_size                     allocation_unit_size
  , state                                    state
  , type                                     type
  , total_mb                                 total_mb
  , (total_mb - free_mb)                     used_mb
  , ROUND((1- (free_mb / total_mb))*100, 2)  pct_used
FROM
    gv$asm_diskgroup
ORDER BY
    name
/

Datafiles of a particular TableSpace
------------------------------------

set pages 200
set lines 200
col tablespace_name for a30
col file_name for a80
select tablespace_name,file_name,bytes/1024/1024 Size_MB,autoextensible,maxbytes/1024/1024 MAXSIZE_MB from dba_data_files where tablespace_name='&TABLESPACE_NAME' order by 1,2;

All schema object details in a tablespace
-----------------------------------------

set pages 9999 lines 300
col tablespace_name format a15
col segment_name format a40
col segment_type format a20
col PARTITION_NAME format a20
col mb format 999,999,999
select    owner
,       tablespace_name
,       segment_name
,       segment_type
,       PARTITION_NAME
,    ceil(sum(bytes) / 1024 / 1024) "Size in MB"
from    dba_segments
where    tablespace_name like '&tablespace_name'
group    by segment_name
order     by ceil(sum(bytes) / 1024 / 1024) desc
/

TABLESPACE DDL
--------------

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

To resize a datafile  (ASM)
---------------------------

ALTER DATABASE DATAFILE '&FILE_NAME' RESIZE 4096M;
ALTER DATABASE DATAFILE '&FILE_NAME' AUTOEXTEND ON MAXSIZE 8G;

To add a new datafile in a tablespace  (ASM)
--------------------------------------------

BEFORE ADDING A DATAFILE WE SHOULD CHECK FOR DUPLICATE DATAFILE For datafile
select tablespace_name,file_name from dba_data_files where file_name like '%&datafilename%';

ALTER TABLESPACE ADD DATAFILE '+DATA' SIZE 100M AUTOEXTEND ON NEXT 100M MAXSIZE UNLIMITED;

To Create a new tablespace  (ASM)
---------------------------------

CREATE TABLESPACE DATAFILE '+DATA' SIZE 100M AUTOEXTEND ON NEXT 100M MAXSIZE UNLIMITED;

Schemas in a tablespace
-----------------------

set pages 999
col "size MB" format 999,999,999
col "Objects" format 999,999,999
select    obj.owner "Owner"
,    obj_cnt "Objects"
,    decode(seg_size, NULL, 0, seg_size) "size MB"
from     (select owner, count(*) obj_cnt from dba_objects group by owner) obj
,    (select owner, ceil(sum(bytes)/1024/1024) seg_size
    from dba_segments group by owner) seg
where     obj.owner  = seg.owner