How to Disable Oracle Scheduler Jobs: Job Queue Processes, Memory, SPFILE, RAC, and Non-SYS Jobs

In Oracle databases, job scheduling allows for the automated execution of tasks, such as routine maintenance and administrative processes. However, there are situations when you might need to disable these scheduled jobs, either temporarily or permanently. This guide will walk you through how to disable Oracle job queue processes using different methods such as memory, SPFILE, and RAC configurations. Additionally, we will look at how to disable non-SYS jobs efficiently.

Disabling Oracle Job Queue Processes in Memory

In some cases, you may want to temporarily disable job queue processes for your Oracle database. This can be done using the MEMORY scope, which makes the change effective only for the current instance until it is restarted.

Command:

ALTER SYSTEM SET job_queue_processes = 0 SCOPE = MEMORY;

This command immediately disables the job queue processes for the current instance of the database, and the setting will be reset to the default upon instance restart.

Disabling Oracle Job Queue Processes in SPFILE and Memory

If you want the change to persist across instance restarts, you can use the SPFILE scope, which updates the server parameter file (SPFILE). This makes the change permanent unless manually modified.

Command:

ALTER SYSTEM SET job_queue_processes = 0 SCOPE = BOTH;

Disabling Job Queue Processes in a RAC Environment

In a Real Application Cluster (RAC) environment, you may want to disable job queue processes for all instances. To do this, specify the SID=’*’ parameter to target all instances.

Command:

ALTER SYSTEM SET job_queue_processes = 0 SCOPE = BOTH SID = '*';

This will disable job queue processes on all nodes in the RAC environment, ensuring consistency across all instances.

Disabling Non-SYS Scheduler Jobs

While disabling job queue processes stops all jobs, you may only want to disable non-SYS jobs. This can be achieved by running a script that selectively disables jobs based on the owner. The following SQL script will generate a set of commands to disable all jobs owned by users other than SYS.

SQL Script:

SET LINES 123 PAGES 234
SET HEAD OFF
SPOOL job_disable.sql

SELECT 'EXECUTE dbms_scheduler.disable(' || owner || '.' || job_name || ');'
FROM dba_scheduler_jobs
WHERE owner != 'SYS';

SPOOL OFF;

Once the script is run, it generates a list of EXECUTE commands to disable all non-SYS jobs, which can be executed to disable them.

Conclusion

Disabling Oracle job queue processes and scheduler jobs can be an essential task in certain database management scenarios, such as performance tuning, maintenance, or troubleshooting. By using the methods outlined above, you can easily control job execution in your Oracle environment, whether you’re working with memory settings, SPFILE configurations, or RAC environments.

Be sure to tailor the commands to your specific requirements—whether disabling all jobs, only non-SYS jobs, or temporarily disabling them during maintenance periods.