Trừ 2 ngày trong sql server - cách dùng hàm DATEDIFF (Transact-SQL)

Để trừ 2 ngày trong SQL Server ( trừ 2 khoảng thời gian trong SQL Server) các bạn có thể dùng hàm DATEDIFF. Cụ thể cách dùng hàm DATEDIFF (Transact-SQL) như sau

Cú Pháp hàm DATEDIFF

DATEDIFF ( datepart , startdate , enddate )

startdate , enddate
là các kiểu dữ liệu time, date, smalldatetime, datetime, datetime2,  datetimeoffset . Trong hàm DATEDIFF chúng ta sẽ lấy enddate trừ cho startdate

Ví dụ cách dùng hàm DATEDIFF

SELECT DATEDIFF(year, '2005-12-31 23:59:59.9999999'
, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(quarter, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(month, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(dayofyear, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(day, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(week, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(hour, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(minute, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(second, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');

SELECT DATEDIFF(millisecond, '2005-12-31 23:59:59.9999999'

, '2006-01-01 00:00:00.0000000');