Retrieves the offset from UTC in hours that the timezone specified
by @datetime represents. Timezones ahead (to the east) of UTC have positive
values, timezones before (to the west) of UTC have negative values.
If @datetime represents UTC time, then the offset is zero.
Retrieves the offset from UTC in hours that the timezone specified by @datetime represents. Timezones ahead (to the east) of UTC have positive values, timezones before (to the west) of UTC have negative values. If @datetime represents UTC time, then the offset is zero.
Return: the offset from UTC in hours