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If set to 'true' datasets are only updated when they have changed. Change is detected by conparing comparing the timestamp in the dataset info file with the modification time of the dataset configuration file. By default this value is 'false' and datasets are always updated. Since the 2018.02 the dataset info file is written to $REGION_HOME$/temp/moduleDataSetsCheckSums when the export dir is sub dir (any level) of the region home.
purgeExportDataSetDirOnUpdate
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