Determines the offset to UTC in effect at the time and in the time
zone of @datetime.
The offset is the number of microseconds that you add to UTC time to
arrive at local time for the time zone (ie: negative numbers for time
zones west of GMT, positive numbers for east).
If @datetime represents UTC time, then the offset is always zero.
Return: the number of microseconds that should be added to UTC to
get the local time
Determines the offset to UTC in effect at the time and in the time zone of @datetime.
The offset is the number of microseconds that you add to UTC time to arrive at local time for the time zone (ie: negative numbers for time zones west of GMT, positive numbers for east).
If @datetime represents UTC time, then the offset is always zero.
Return: the number of microseconds that should be added to UTC to get the local time