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Average of timestamp/Datetime in my query? Please help?
select a.job_name,endtime,to_char(endtime,'HH24:MI:SS') as endtime_1
   from OPTOOLS.R11_JOB_PROD_VW a, OPTOOLS.R11_JOB_RUNS_PROD_VW b
   where
   a.joid=b.joid and a.job_name in ('hh_p_hkc_isrs_gim_trd_ld_bx') and rownum <= 30
   and status = 'SUCCESS'
   order by endtime desc;

SELECT a.job_name, AVG(endtime)
FROM (...)
WHERE (...)
GROUP BY a.job_name

SELECT
  FROM_UNIXTIME(AVG(UNIX_TIMESTAMP(endtime)))
FROM
  ...
  ...
  ...