Oracle Cron Jobs

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I can't think of few things in our industry more worthless but still in use than cron jobs. Cron jobs, by almost any measure, are both obsolete and functionally deficient. In the following rant I am going to publicly make a point that has needed to be made for a very long time.

Characteristic Scheduler Job 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 PL/SQL SQL plus a shell scripting language
Load Balance Aware RAC Aware RAC Ignorant
Failover Aware RAC Aware RAC Ignorant
Job Chaining Fully supported Not available
Flexibility Job modifiable while running Jobs can not be modified while running
File Watching Fully integrated Non-existent
Job Grouping Fully integrated job grouping Non-existent
Job Windowing Jobs can be run solely within temporal windows Long running jobs have no windowing rules
Exception Handling Fully integrated Non-existent
Outage Aware Will never try to run if the database is not open Will try to run even if the local databases has crashed and burned
Reporting Support Full support for SQL and a wide variety of third-party reporting tools None
Messaging Support True and fully integrated with JMS through AQ False
Bug Support Support available from Oracle Corp ROFLOL

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 it fails.

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.
Now that you have hopefully 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

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