DATEDIFF

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Syntax

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Days (scalar)

datediff(end, start)

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Units (scalar)

datediff(unit, start, end)

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Arguments

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Days

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Units

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Returns

• Type: BIGINT
• NULL behavior: Returns NULL if a temporal argument or unit is NULL, or a timestamp cannot be represented by the temporal conversion. An unknown non-NULL unit raises an error.

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Properties

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Units

• Input unit: Calendar dates or timestamps
• Output unit: Days for the two-argument form; specified complete units for the three-argument form

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Usage notes

• Two-argument order is (end,start); three-argument order is (unit,start,end).
• Two arguments compare local calendar dates and discard time-of-day; three arguments count complete elapsed units.
• Calendar year/quarter/month results use complete calendar units, not a fixed number of seconds. Negative differences are possible.

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Examples

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Cross a date boundary

SELECT datediff(TIMESTAMP '2024-07-16 00:01:00', TIMESTAMP '2024-07-15 23:59:00') AS result;

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Complete elapsed hours

SELECT datediff('hour', TIMESTAMP '2024-07-15 22:00:00', TIMESTAMP '2024-07-16 00:30:00') AS result;