Oracle DBA: DBA_JOBS facts

Query to see the jobs running through dba_jobs

select /*+ rule */ * from dba_jobs_running;

or

select /*+ ordered */ * from dba_jobs_running;

Common Reason why jobs don't execute automatically and as scheduled
1) select instance_name,logins from v$instance;
If the logins=RESTRICTED, then:
alter system disable restricted session;

2) check the JOB_QUEUE_PROCESSES
show parameter JOB_QUEUE_PROCESSES
It should greater then 0

3)Is the job BROKEN?
select job,broken from dba_jobs where job=;
If broken, then check the alert log and trace files to diagnose the issue

4) _SYSTEM_TRIG_ENABLED=FALSE
Check if _system_enabled_trigger=false
col parameter format a25
col value format a15
select a.ksppinm parameter,b.ksppstvl value from x$ksppi a,x$ksppcv b
Where a.indx=b.indx and ksppinm=’_system_trig_enabled’;
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Source:-http://appsoracle.blogspot.com/2011/04/oracle-dba-dbajobs-facts.html
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