Oracle | Cron Jobs

Oracle Cron Jobs Version 21c

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<RANT>

I can think of few things in our industry more worthless but still in common use than the Oracle cron job. Cron jobs, by essentially any measure, are both obsolete and functionally deficient. In this following rant I am going to publicly make a point that has needed to be made for a very long time.

Characteristic	Database Scheduler Job	*NIX Cron Job
Operating system support	True	True
Operating System interchangeable	Jobs can be moved, seamlessly, between operating systems	Jobs require rewrite between operating systems
Windows Support	True	False
O/S Access Required	False	True
DB Access Required	True	True
Languages Required	SQL plus minimal PL/SQL	SQL plus a shell scripting language
RAC Load Balance Aware	TRUE	FALSE
RAC Failover Aware	TRUE	FALSE
Data Guard Switchover Aware	TRUE	FALSE
Data Guard Failover Aware	TRUE	FALSE
Backed up by RMAN	TRUE	FALSE
Job Chaining	Fully supported	No support available
Flexibility	Jobs may be modifiable while running	Jobs cannot be modified while running
File Watching	Fully integrated	Non-existent
Job Grouping	Fully integrated	Non-existent
Job Windowing	Jobs can be run solely within defined temporal windows	Long running jobs have no windowing rules
Exception Handling	Fully integrated	Non-existent
Metadata Collection	Extensive metadata collected for every run or failure	Non-existent
Outage Aware	Will never try to run if the database is not open	Totally unaware of whether the database exists
Reporting Support	Full support for SQL and a wide variety of third-party reporting tools	None
Messaging Support	Fully integrated with JMS through Advanced Queuing	False
Bug Support	Support available from Oracle Corp	ROFLOL
Licensing Cost	None	None

When I add up the score I see cron capable of doing only one thing well ... running jobs in the O/S. At all but two other criteria cron is a miserable failure.

Still want to write a cron job? Be my guest but don't expect a non-Cretaceous DBA to support or maintain it any more than you should expect to find "VAX" or "PDP 11" on their CV.

</RANT>

Now that you have, I hope, been convinced to abandon the Paleolithic insanity that is cron the following link may help you locate the vermin so you can exterminate them. Linux: List / Display All Cron Jobs

# crontab -u oracle -l