Returns the number of hours since an arbitrary starting date and time, the number of whole hours between two specified times, or adds the specified integer-expression number of hours to a time.
HOURS ( datetime-expression | datetime-expression, datetime-expression | datetime-expression, integer-expression )
datetime-expression A date and time.
integer-expression The number of hours to be added to the datetime-expression. If integer-expression is negative, the appropriate number of hours are subtracted from the date/time. If you supply an integer expression, the datetime-expression must be explicitly cast as a datetime data type.
For information on casting data types, see the section “CAST function [Data type conversion]”.
The following statement returns the value 17518758:
SELECT HOURS( '1998-07-13 06:07:12' ) FROM iq_dummy
The following statement returns the value 4, to signify the difference between the two times:
SELECT HOURS( '1999-07-13 06:07:12', '1999-07-13 10:07:12' ) FROM iq_dummy
The following statement returns the datetime value 1999-05-13 02:05:07.000.
SELECT HOURS( CAST( '1999-05-12 21:05:07' AS DATETIME ), 5 ) FROM iq_dummy
The second syntax returns the number of whole hours from the first date/time to the second date/time. The number may be negative.