ps-dont-set-content-to-nil-while-aggregating
Don't update aggregated_at nor content if there're no log pa…
When the aggregation process runs we first gather all of the ids to aggregate and then we run aggregate code on each of the logs. If a user restarts a job after the ids are fetched, but before the log for the job was aggregated, the restart will clean log parts. In such case we would set content to NULL and aggregated_at to current time.
This commit changes the query to aggregate log to rerun log_parts check, meaning that the UPDATE will not update anything unless a log with parts is available.