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If an expiryTime is defined at the TimeSeriesSet level, the time series blobs will get this expiry time, no matter what the workflow says.
If the timeseries is of an external type, the timeseries will also stay accessible. If a time series is of the simulated type, data access has to go through a query where the taskrun record plays a major role. This taskrun record expirytime is defined by the workflow. If the taskrun record is removed, the simulated data has become orphan as it has become inaccessible.
Preserving taskrun information for access to timeseries
Timeseries in the database without taskruns are referred to as "orphaned timeseries". Note that simulated timeseries are not meaningful without taskrun information and should never be orphaned. Only external timeseries can be orphaned, but without taskruns they can not be amalgamated (merged) any more. In order to preserve taskruns longer than the default of ten days, the taskruns expirytime should be increased.
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