Difference between DateTime and DateTime2 in SQL Server

Create a new column (ALTER TABLE) then run an UPDATE on it. UPDATE MyTable SET NewIntColumn = DATEDIFF(SECOND, '19000101', MyDateTimeColumn).

Given a date or datetime expr , returns the number of seconds since the year 0. If expr is not a valid date or datetime value (including NULL ), it returns NULL ... MySQL Server Time Zone... · 11.5 Expressions · 9.0

Defines a date that is combined with a time of day with fractional seconds that is based on a 24-hour clock. Avoid using datetime for new work.

您必須明確地將字串轉換成datetime 或smalldatetime 類型，才能使用 YDM 格式。 ... seconds = DATEDIFF(s, @date1, @date2); IF DATEADD(s, -@seconds ... 語法 · 引數

Use DATEPART : (DATEPART(HOUR, GETDATE()) * 3600) + (DATEPART(MINUTE, GETDATE()) * 60) + (DATEPART(SECOND, GETDATE())).

Use the specific date that you have selected as epoch: convert(datetime, dateadd(ms, dateTimeInMilliseconds, '2010-01-01'))

SQL Server DATEDIFF function returns the difference in seconds, minutes, hours, days, weeks, months, quarters and years between 2 datetime values.

The time string can be directly assigned to a datetime variable as 1900-01-01 20:10:10: DECLARE @time datetime = '20:10:10'.

CONVERT DATETIME to TIME and remove seconds and milliseconds ; @StartTime1 TIME = '17:41:00.0000000'; ; @StartTime2 DATETIME = '2016-09-22 17:41: ...

The TIME_TO_SEC() function converts a time value into seconds. Syntax: TIME_TO_SEC(time) Parameter Values: Technical Details: More Examples: