Function dateadd adalah sebuah function yang disediakan oleh Sybase untuk mencari suatu tanggal dari parameter tanggal tertentu, bedasarkan penambahan atau pengurangan parameter hari, bulan dan tahun.
numeric
date expression
Adaptive Server automatically converts between character and datetime
values when necessary
(for example, when you compare a character value to a datetime value).
Using the date part weekday or dw with dateadd is not logical,
and produces spurious results.
Use day or dd instead.
Table 2-7: date_part recognized abbreviations
dateadd
Description
Returns the date produced by adding a given number of years, quarters, hours,
or other date parts to the specified date.
or other date parts to the specified date.
Syntax
dateadd(date_part, integer, date expression)
Parameters
is a date part or abbreviation.
For a list of the date parts and abbreviations recognized by Adaptive Server, see “Date parts”.
For a list of the date parts and abbreviations recognized by Adaptive Server, see “Date parts”.
numeric
is an integer expression.
date expression
is an expression of type datetime, smalldatetime, date, time,
or a character string in a datetime format.
or a character string in a datetime format.
Examples
Example 1
Displays the new publication dates when the publication dates of all the books
in the titles table slip by 21 days:
in the titles table slip by 21 days:
select newpubdate = dateadd(day, 21, pubdate) from titles
Example 2
Add one day to a date:
declare @a dateselect @a = "apr 12, 9999"select dateadd(dd, 1, @a)
--------------------------
Apr 13 9999
--------------------------
Apr 13 9999
Example 3
Add five minutes to a time:
select dateadd(mi, 5, convert(time, "14:20:00"))
--------------------------
2:25PM
--------------------------
2:25PM
Example 4
Add one day to a time and the time remains the same:
declare @a timeselect @a = "14:20:00"select dateadd(dd, 1, @a)
--------------------------
2:20PM
--------------------------
2:20PM
Example 5
Although there are limits for each date_part, as with datetime values,
higher values can be added resulting in the values rolling over to the next significant field:
higher values can be added resulting in the values rolling over to the next significant field:
--Add 24 hours to a datetime
select dateadd(hh, 24, "4/1/1979")
--------------------------
Apr 2 1979 12:00AM
--Add 24 hours to a date
select dateadd(hh, 24, "4/1/1979")
-------------------------
Apr 2 1979
select dateadd(hh, 24, "4/1/1979")
--------------------------
Apr 2 1979 12:00AM
--Add 24 hours to a date
select dateadd(hh, 24, "4/1/1979")
-------------------------
Apr 2 1979
Usage
·dateadd, a date function, adds an interval to a specified date.
For more information about date functions, see “Date functions”.
For more information about date functions, see “Date functions”.
·dateadd takes three arguments: the date part, a number, and a date.
The result is a datetime value equal to the date plus the number of date parts.
The result is a datetime value equal to the date plus the number of date parts.
·If the date argument is a smalldatetime value, the result is also a smalldatetime.
You can use dateadd to add seconds or milliseconds to a smalldatetime,
but it is meaningful only if the result date returned by dateadd
changes by at least one minute.
You can use dateadd to add seconds or milliseconds to a smalldatetime,
but it is meaningful only if the result date returned by dateadd
changes by at least one minute.
·Use the datetime datatype only for dates after January 1, 1753.
datetime values must be enclosed in single or double quotes.
Use the date datatype for dates from January 1, 0001 to 9999.
date must be enclosed in single or double quotes.
Use char, nchar, varchar or nvarchar for earlier dates.
Adaptive Server recognizes a wide variety of date formats. For more information,
see “User defined datatypes” and “Datatype conversion functions”.
datetime values must be enclosed in single or double quotes.
Use the date datatype for dates from January 1, 0001 to 9999.
date must be enclosed in single or double quotes.
Use char, nchar, varchar or nvarchar for earlier dates.
Adaptive Server recognizes a wide variety of date formats. For more information,
see “User defined datatypes” and “Datatype conversion functions”.
Adaptive Server automatically converts between character and datetime
values when necessary
(for example, when you compare a character value to a datetime value).
Using the date part weekday or dw with dateadd is not logical,
and produces spurious results.
Use day or dd instead.
Table 2-7: date_part recognized abbreviations
Date part
|
Abbreviation
|
Values
|
Year
|
yy
|
1753-9999 (datetime)
1900-2079 (smalldatetime)
0001-9999 (date)
|
Quarter
|
qq
|
1-4
|
Month
|
mm
|
1-12
|
Week
|
wk
|
1054
|
Day
|
dd
|
1-7
|
dayofyear
|
dy
|
1-366
|
Weekday
|
dw
|
1-7
|
Hour
|
hh
|
0-23
|
Minute
|
mi
|
0-59
|
Second
|
ss
|
0-59
|
millisecond
|
ms
|
0-999
|
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