Time Function Returns a Numeric Value
Returns the value of the time_value in hours (0-23 or 3,600,000). If the time_value is blank, then returns 3,600,000 (i.e., the number of milliseconds in one hour). If the time_value is equal to "hh:mm AM:, then returns -1.

Examples:

HOUR( )

Returns 3,600,000 (without the commas).

HOUR(TIME)

Returns 13 if the current system time is between 01:00 PM and 01:59 PM.

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