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A unique sync job is required at the end of every set of processes running in parallel (see Setting_up_a_sync_job), when further nodes in the job chain after the sync node are only to be processed after all the jobs (tasks) that are to be carried out in parallel have been completed without errors.
Each sync job has to be unique within a JobScheduler instance - and within a job chain as long as a cross-over pattern has not been implemented (see Synchronizaton_Synchronisation of _ Job _ Chains).
For more information see the documentation for the JobSchedulerSynchronizeJobChains job.
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