问题
I have read the document already but i do not fully understand The default precision is datetime2(7) is 7 represent the precision of nanosecond?
回答1:
The resolution of the default precision (7) datetime2 type is 100 nanoseconds.
An excellent reference for things date/time is : The ultimate guide to the datetime datatypes
回答2:
No, the number represents the number of digits preserved after the decimal point for the seconds. 3 would be millisecond, 6 microsecond and 7 equivalent to a precision of 100 nanoseconds.
来源：https://stackoverflow.com/questions/7738364/is-number-after-datetime2-is-for-nanosecond-purpose