Is it safe to delete rows in the LSW_TASK table where the column bpd_instance_id is null? The subject column of the row starts with "Error executing."
When an undercover agent (UCA) or system activity fails, a record is inserted into the LSW_TASK table to record the failure. The instance is marked as FAILED. These instances need to be restarted through the Process Inspector (web or IBM Process Designer) or REST API. While you purge closed tasks and instances, you might notice that some closed tasks are not associated with an instance.
On certain failures like a UCA retry, business process definition (BPD) timer retry, or system lane failure, a record is inserted into the LSW_TASK table. A BPD instance is not associated with this notification. Instead, it becomes an item in the Portal inbox for the administrator. tw_admin is the default user who can see these items.