How big are my tablespaces, and how much space is really being used?

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Article ID: 160313

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Updated On:

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Data Loss Prevention Enforce

Issue/Introduction

How much space has been allocated to the database, and how much of that space is really being used?

Resolution

Oracle likes to take up space and never let go.  So, just how much space has been allocated to your database, and how much of that is REALLY being used?  The following script lists the amount of space allocated and percentage free for each tablespace (with the exception of TEMP).

Run the following from SQLPLUS as sysdba to:

set feed off
set linesize 100
set pagesize 200
SELECT F.TABLESPACE_NAME,
TO_CHAR ((T.TOTAL_SPACE - F.FREE_SPACE),'999,999') "USED (MB)",
TO_CHAR (F.FREE_SPACE, '999,999') "FREE (MB)",
TO_CHAR (T.TOTAL_SPACE, '999,999') "TOTAL (MB)",
TO_CHAR ((ROUND ((F.FREE_SPACE/T.TOTAL_SPACE)*100)),'999')||' %' PER_FREE
FROM (
SELECT TABLESPACE_NAME,
ROUND (SUM (BLOCKS*(SELECT VALUE/1024
FROM V$PARAMETER
WHERE NAME = 'db_block_size')/1024)
) FREE_SPACE
FROM DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME
) F,
(
SELECT TABLESPACE_NAME,
ROUND (SUM (BYTES/1048576)) TOTAL_SPACE
FROM DBA_DATA_FILES
GROUP BY TABLESPACE_NAME
) T
WHERE F.TABLESPACE_NAME = T.TABLESPACE_NAME
/

This script is identical to the first except it shows the percentage used for each tablespace:

set feed off
set linesize 100
set pagesize 200
SELECT F.TABLESPACE_NAME,
TO_CHAR ((T.TOTAL_SPACE - F.FREE_SPACE),'999,999') "USED (MB)",
TO_CHAR (F.FREE_SPACE, '999,999') "FREE (MB)",
TO_CHAR (T.TOTAL_SPACE, '999,999') "TOTAL (MB)",
TO_CHAR ((ROUND ((F.FREE_SPACE/T.TOTAL_SPACE)*100)),'999')||' %' PER_FREE
FROM (
SELECT TABLESPACE_NAME,
ROUND (SUM (BLOCKS*(SELECT VALUE/1024
FROM V$PARAMETER
WHERE NAME = 'db_block_size')/1024)
) FREE_SPACE
FROM DBA_FREE_SPACE
GROUP BY TABLESPACE_NAME
) F,
(
SELECT TABLESPACE_NAME,
ROUND (SUM (BYTES/1048576)) TOTAL_SPACE
FROM DBA_DATA_FILES
GROUP BY TABLESPACE_NAME
) T
WHERE F.TABLESPACE_NAME = T.TABLESPACE_NAME
/