Page History

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Note that this mechanism allows to add various details to synchronizing users: password, attributes, resources, roles, etc.

How to clean up

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tasks?

The easiest way to perform this cleaning is via the admin console, by leveraging the bulk action feature (leftmost checkbox column, available in many data tables, then click on the blue gear on the bottom and 
choose the delete icon). 

Via REST, task execution removal (for any kind of task: propagation, synchronization, scheduled, notification) can be performed as 

GET /rest/task/execution/delete/{executionIdtaskId}

or

DELETE /cxf/tasks/executions/{executionIdtaskId} (1.1.X)
DELETE /rest/tasks/executions/{executionIdtaskId} (>= 1.2.X)

Consider anyway that task execution storage can be controlled by setting the trace level to NONE, FAILURES or SUMMARY instead of ALL (which is the default) on the corresponding Task or Notification.