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To import only data for a given period of time specify either a relative period or an absolute period in the import configuration file. See relativeViewPeriod, startDateTime and endDateTime for more information. The import will first search the metadata of each file that needs to be imported from the OPeNDAP server. Then for each file that contains data within the specified period, only the data within the specified period will be imported. The start and end of the period are both inclusive.
This can be used to import only the relevant data if only data for a given period is needed, which can save a lot of time. However, for this to work the import still needs to search through all the metadata of the file(s) to be imported. So for large catalogs that contain a lot of files, it can still take a lot of time for the import to download all the required metadata from the OPeNDAP server.
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