The process modeller allows you to delete a deployed process so that it is no longer available to use by the workflow engine.
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Deleting Instances
When you delete a process, all running and all historic instances will be deleted too.
Deleting a process that includes a call activity which starts another process will also delete any instances of the target/child process.
Scheduled Task
The Scheduled Tasks section lets you set up a task that will delete terminated instances. The default settings delete any closed instances older than 365 days from when the task runs.
When the task runs a history is logged in the platform's History service, recording the number of instances deleted. This history has a "labela" value of "Workflow". For example:
{
"labela": "Workflow",
"labelb": "1173-1551-6349-6855",
"labelc": null,
"labeld": null,
"labele": null,
"created": 1548802808323,
"lastupdated": 1548802808323,
"id": "0555e386-25f2-4bc8-a202-3fb4049941d3",
"sealed": false,
"subject": null,
"events": [{
"pos": [1, 1],
"event": {
"description": "13 records older than 365 days purged.",
"event": "PURGEPROCESSINSTANCES"
},
"fpos": [1, 1],
"timestamp": 1548802808323
}]
}