Finding free/used temporary table space in Oracle

If you’re a freak who work around with Oracle as backend, you would face the sitution where the oracle temporary space would be exhausted.

The usage temporary tablespace can’t be found out exactly using DBA_FREE_SPACE. To find out the true value of temporary table space we may need to use V$TEMP_SPACE_HEADER data dictonary.

SELECT   tablespace_name, SUM (bytes_used), SUM (bytes_free)
    FROM v$temp_space_header
GROUP BY tablespace_name;

If you’re looking out to find out the usage of other table space we need to use the following script.

CLEAR
SET HEAD ON
SET VERIFY OFF
SPOOL file
COL tspace form a25 Heading "Tablespace"
COL tot_ts_size form 99999999999999 Heading "Size (Mb)"
COL free_ts_size form 99999999999999 Heading "Free (Mb)"
COL ts_pct form 9999 Heading "% Free"
COL ts_pct1 form 9999 Heading "% Used"
BREAK on report
COMPUTE sum of free_ts_size on report
COMPUTE sum of tot_ts_size on report
SELECT                                                            /* + RULE */
         df.tablespace_name tspace, df.BYTES / (1024 * 1024) tot_ts_size,
         SUM (fs.BYTES) / (1024 * 1024) free_ts_size,
         NVL (ROUND (SUM (fs.BYTES) * 100 / df.BYTES), 1) ts_pct,
         ROUND ((df.BYTES - SUM (fs.BYTES)) * 100 / df.BYTES) ts_pct1
    FROM dba_free_space fs,
         (SELECT   tablespace_name, SUM (BYTES) BYTES
              FROM dba_data_files
          GROUP BY tablespace_name) df
   WHERE fs.tablespace_name(+) = df.tablespace_name
GROUP BY df.tablespace_name, df.BYTES
UNION ALL
SELECT                                                            /* + RULE */
         df.tablespace_name tspace, fs.BYTES / (1024 * 1024) tot_ts_size,
         SUM (df.bytes_free) / (1024 * 1024) free_ts_size,
         NVL (ROUND ((SUM (fs.BYTES) - df.bytes_used) * 100 / fs.BYTES),
              1
             ) ts_pct,
         ROUND ((SUM (fs.BYTES) - df.bytes_free) * 100 / fs.BYTES) ts_pct1
    FROM dba_temp_files fs,
         (SELECT   tablespace_name, bytes_free, bytes_used
              FROM v$temp_space_header
          GROUP BY tablespace_name, bytes_free, bytes_used) df
   WHERE fs.tablespace_name(+) = df.tablespace_name
GROUP BY df.tablespace_name, fs.BYTES, df.bytes_free, df.bytes_used
ORDER BY 4 DESC
/
SPOOL off

To find the size of table different technique has to be used.