SQL Time Date function

getdate () function

Returns the current date and time of the system in the default format of datetime

Syntax format: getdate ()

Year () Month () Day () function

Returns the year, month, and date value in Date_expression

Syntax format: year/month/day (date_expression datetime/varchar) Returns int

Example: Year (GETDATE ()), year (' 2016-05-01 ')

datename () function

Returns the specified part of a date as a string

Syntax format: datename (datepart,date_expression)

Example: Datename (Month,getdate ()), Datename (year, ' 2016-05-01 ')

datepart () function

Returns the specified part of a date as an integral type

Syntax format: DATEPART (datepart,date_expression)

DateAdd () function

Returns the new date specified by date plus the specified extra date interval number

Syntax format: DATEADD (datepart,number,date)

Cases:

Add 2 months on the specified date

DATEADD (mm,2, ' 2016-05-11 ') 2016-07-11

DATEADD (Mm,2,getdate ())

Minus 2 months on a specified date

DATEADD (mm,-2, ' 2016-05-11 ')

DATEADD (Mm,-2,getdate ())

DateDiff () function

Returns the datepart difference between the specified two dates, that is, the gap value of StartDate and EndDate, and the result is a signed integer value

Syntax format: DateDiff (Datepart,startpart,endpart)

Example: DATEDIFF (DD, ' 2016-05-01 ', ' 2016-07-10 ') returns 70, the number of days gap value is 70

DATEDIFF (MM, ' 2016-05-01 ', ' 2016-07-10 ') returns 2, month gap value is 2

SQL Time Date function