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In case, the added table does not contain Duration type fields, but one or more Referenced fields of this type are added - an option will appear too:
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What data format to choose for export
By default, when Duration fields are added and no “Duration in seconds” or “Use display value” are turn on, data will be exported in Edm.Duration format:
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NOTE: please take into account that String format for Display value can be also seen in the backend part:
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Restriction
It is impossible to apply both “Duration in seconds” and “Use display value” at once. They are mutually exclusive options. It means, that in case if “Duration in seconds” is turned on “Use display value” is turned off:
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