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• Inputs must be column references.
• The first value is used as the baseline to compare the date values.
• Results are calculated to the integer value that is closest to and lower than the exact total; remaining decimal values are dropped.

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• Date values must be column references.
• If date1 and date2 have a specified time zone offset, DATEDIF the function calculates the  the difference including the timezone offsets.
• If date1 does not have a specified time zone but date2 does, DATEDIF uses the function uses the local time in the same time zone as date2 to calculate the difference. DATEDIF returns The functions returns the difference without the time zone offset.

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