According to msdn the general standart for datetime is
select convert(datetime,'19781222',112) //YYYYMMDD
So if i want to insert into datetime this value i can do it by
update [Readings] set [StartDate] = '19781222'
But what about time ? how do i add the Time to the YYYYMMDD ?
Question 2 : how do i update only the time in DateTime ?
1st part:
2nd:
The ultimate guide to the datetime datatypes