Some Basic Scripts Used

SQL Query used to check the Table spaces usage and allocation:

Below Lines are to set the report format: 

SQL> SET LINe 200

SQL> SET PAGES 100

SQL> col STATUS for a10

SQL> col ACTUAL_START_DATE for a35

SQL> col RUN_DURATION for a25

SQL> col file_name for a60

Below are the optional things just to get SUM at end:

SQL> break on report

SQL> compute SUM of MB_FREE ON REPORT

SQL> compute sum of MB_ALLOCATED ON report

SQL> compute sum of MB_USED ON REPORT

Query used to check the Table space Usage, Free and Allocation 
SQL>
SELECT * FROM( SELECT 
c.tablespace_name, 
ROUND(a.bytes/(1024*1024),2) MB_Allocated, 
ROUND((a.bytes-b.bytes)/(1024*1024),2) MB_Used, 
ROUND(b.bytes/(1024*1024),2) MB_Free, 
ROUND(b.bytes/a.bytes * 100,2) tot_Pct_Free, 
ROUND((a.bytes-b.bytes)/a.bytes,2) * 100 tot_Pct_Used 
FROM 
(SELECT tablespace_name, SUM(ddf.bytes) bytes FROM sys.DBA_DATA_FILES ddf GROUP BY tablespace_name) a,
(SELECT ddf.tablespace_name, NVL(SUM(dfs.bytes),0) bytes FROM sys.DBA_DATA_FILES ddf, sys.DBA_FREE_SPACE dfs WHERE ddf.tablespace_name = dfs.tablespace_name AND ddf.file_id = dfs.file_id GROUP BY ddf.tablespace_name) b,
sys.DBA_TABLESPACES c
WHERE 
a.tablespace_name = b.tablespace_name AND a.tablespace_name = c.tablespace_name ) 
WHERE 
tot_Pct_Used >=0
ORDER BY 
tablespace_name
/

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