Below script can be configured in crontab to send a notification to the support DBAs in case tablespace usage crosses a threshold.
1. First, make the below .sql file, which will be used inside the shell script.
In this script we have defined the threshold as 90%. You can change it as per your requirement.
cat /export/home/oracle/Housekeeping/scripts/tablespace_alert.sql
set feedback off
set pagesize 70;
set linesize 2000
set head on
COLUMN Tablespace        format a25 heading 'Tablespace Name'
COLUMN autoextensible         format a11              heading 'AutoExtend'
COLUMN files_in_tablespace    format 999             heading 'Files'
COLUMN total_tablespace_space format 99999999 heading 'TotalSpace'
COLUMN total_used_space       format 99999999 heading 'UsedSpace'
COLUMN total_tablespace_free_space format 99999999 heading 'FreeSpace'
COLUMN total_used_pct              format 9999      heading '%Used'
COLUMN total_free_pct              format 9999     heading '%Free'
COLUMN max_size_of_tablespace      format 99999999 heading 'ExtendUpto'
COLUM total_auto_used_pct         format 999.99      heading 'Max%Used'
COLUMN total_auto_free_pct         format 999.99      heading 'Max%Free'
WITH tbs_auto AS
     (SELECT DISTINCT tablespace_name, autoextensible
                 FROM dba_data_files
                WHERE autoextensible = 'YES'),
     files AS
     (SELECT   tablespace_name, COUNT (*) tbs_files,
               SUM (BYTES/1024/1024) total_tbs_bytes
          FROM dba_data_files
      GROUP BY tablespace_name),
     fragments AS
     (SELECT   tablespace_name, COUNT (*) tbs_fragments,
               SUM (BYTES)/1024/1024 total_tbs_free_bytes,
               MAX (BYTES)/1024/1024 max_free_chunk_bytes
          FROM dba_free_space
      GROUP BY tablespace_name),
     AUTOEXTEND AS
     (SELECT   tablespace_name, SUM (size_to_grow) total_growth_tbs
          FROM (SELECT   tablespace_name, SUM (maxbytes)/1024/1024 size_to_grow
                    FROM dba_data_files
                   WHERE autoextensible = 'YES'
                GROUP BY tablespace_name
                UNION
                SELECT   tablespace_name, SUM (BYTES)/1024/1024 size_to_grow
                    FROM dba_data_files
                   WHERE autoextensible = 'NO'
                GROUP BY tablespace_name)
      GROUP BY tablespace_name)
SELECT c.instance_name,a.tablespace_name Tablespace,
       CASE tbs_auto.autoextensible
          WHEN 'YES'
             THEN 'YES'
          ELSE 'NO'
       END AS autoextensible,
       files.tbs_files files_in_tablespace,
       files.total_tbs_bytes total_tablespace_space,
       (files.total_tbs_bytes - fragments.total_tbs_free_bytes
       ) total_used_space,
       fragments.total_tbs_free_bytes total_tablespace_free_space,
       round((  (  (files.total_tbs_bytes - fragments.total_tbs_free_bytes)
           / files.total_tbs_bytes
          )
        * 100
       )) total_used_pct,
       round(((fragments.total_tbs_free_bytes / files.total_tbs_bytes) * 100
       )) total_free_pct
  FROM dba_tablespaces a,v$instance c , files, fragments, AUTOEXTEND, tbs_auto
WHERE a.tablespace_name = files.tablespace_name
   AND a.tablespace_name = fragments.tablespace_name
   AND a.tablespace_name = AUTOEXTEND.tablespace_name
   AND a.tablespace_name = tbs_auto.tablespace_name(+)
and (((files.total_tbs_bytes - fragments.total_tbs_free_bytes)/ files.total_tbs_bytes))* 100 > 90
order by total_free_pct;
2. Now prepare the shell script:
At the beginning of the script, we need to define the env variables like ORACLE_HOME, PATCH, LD_LIBRARY_PATH, ORACLE_SID.
Below is the final script(tablespace_threshold.ksh)
cat /export/home/oracle/Housekeeping/scripts/tablespace_threshold.ksh #!/bin/sh export ORACLE_HOME=/u01/app/oracle/product/12.1.0/dbhome_1 export PATH=$ORACLE_HOME/bin:$PATH export LD_LIBRARY_PATH=$ORACLE_HOME/lib export ORACLE_SID=PRODDB cd /export/home/oracle/Housekeeping/scripts logfile=/export/home/oracle/Housekeeping/scripts/Tablespace_alert.log cnt1=`ps -ef|grep pmon|grep $ORACLE_SID|wc -l` if [ $cnt1 -eq 1 ]; then sqlplus -s "/as sysdba" > /dev/null << EOF spool $logfile @/export/home/oracle/Housekeeping/scripts/tablespace_alert.sql spool off exit EOF # If there are more then these two lines in the output file, mail it. count=`cat $logfile|wc -l` #echo $count if [ $count -ge 4 ]; then mailx -s "TABLESPACE ALERT FOR PROD DB " support@dbaclass.com <$logfile fi fi
3. Now configure in crontab:
0,15,30,45 * * * * /export/home/oracle/Housekeeping/scripts/tablespace_threshold.ksh > /export/home/oracle/Housekeeping/logs/ts_alert.log 2>&1
If this article is helpful to you, please provide comment or write to us support@dbaclass.com.

Very nice
looks this script will work only if one database exist on server. If we need to make it work for all the databases on server then can you please modify it
We can pass TNS ALISAS IN FOR LOOP AND RUN THE SCRIPT, Still i will shared the complete script.
Hello Admin,
Thank you very much for your scripts. Would you mind sharing the script for multiple databases.
Thanks & Regards
Sai