Create a CTE list of dates on the fly - SQL

CTE list of dates on the fly:

WITH D AS
(
SELECT number AS rn FROM master.dbo.spt_values
WHERE type = 'P' AND number BETWEEN 0 AND 29
)
SELECT DATEADD(dd, -D.rn, DATEADD(dd, DATEDIFF(dd,0,GETDATE()), 0)) AS ReportDate
FROM D;


2000/pre CTE solution here

Create a list of dates on the fly - SQL

I've recently had the requirement to produce a list of the last 30 days on the fly (I didn't have the option to refer to a 'Numbers' table). This was to be used as a 'Command' in Crystal Reports and joined to a database table to produce 'missing dates'.

Using the system table, spt_values, the first stage was to produce a list of numbers:

SELECT number AS rn FROM master.dbo.spt_values
WHERE type = 'P' AND number BETWEEN 0 AND 29

This is then extended to produce a list of the last 30 dates.

SELECT DATEADD(dd, -D.rn, DATEADD(dd, DATEDIFF(dd,0,GETDATE()), 0)) AS ReportDate
FROM (
SELECT number AS rn FROM master.dbo.spt_values
WHERE type = 'P' AND number BETWEEN 0 AND 29
) AS D

This was with help from both Chris Morris & Kevin McKelvey at http://www.sqlservercentral.com/

CTE solution here



 

Useful date formulas - SQL

This was posted on http://www.sqlservercentral.com/blogs/lynnpettis/archive/2009/03/25/some-common-date-routines.aspx

declare @ThisDate datetime;

set @ThisDate = getdate();

select dateadd(dd, datediff(dd, 0, @ThisDate), 0) -- Beginning of this day
select dateadd(dd, datediff(dd, 0, @ThisDate) + 1, 0) -- Beginning of next day
select dateadd(dd, datediff(dd, 0, @ThisDate) - 1, 0) -- Beginning of previous day
select dateadd(wk, datediff(wk, 0, @ThisDate), 0) -- Beginning of this week (Monday)
select dateadd(wk, datediff(wk, 0, @ThisDate) + 1, 0) -- Beginning of next week (Monday)
select dateadd(wk, datediff(wk, 0, @ThisDate) - 1, 0) -- Beginning of previous week (Monday)
select dateadd(mm, datediff(mm, 0, @ThisDate), 0) -- Beginning of this month
select dateadd(mm, datediff(mm, 0, @ThisDate) + 1, 0) -- Beginning of next month
select dateadd(mm, datediff(mm, 0, @ThisDate) - 1, 0) -- Beginning of previous month
select dateadd(qq, datediff(qq, 0, @ThisDate), 0) -- Beginning of this quarter (Calendar)
select dateadd(qq, datediff(qq, 0, @ThisDate) + 1, 0) -- Beginning of next quarter (Calendar)
select dateadd(qq, datediff(qq, 0, @ThisDate) - 1, 0) -- Beginning of previous quarter (Calendar)
select dateadd(yy, datediff(yy, 0, @ThisDate), 0) -- Beginning of this year
select dateadd(yy, datediff(yy, 0, @ThisDate) + 1, 0) -- Beginning of next year
select dateadd(yy, datediff(yy, 0, @ThisDate) - 1, 0) -- Beginning of previous year

Auxiliary Calendar table - SQL

This code is derived from a useful article by Todd Fifield at SQLServerCentral.com and has been modified to include columns based on the ISO8601 date and times standard (here and here).

IF OBJECT_ID('dbo.CalendarDay') IS NOT NULL
DROP TABLE dbo.CalendarDay;
GO

CREATE TABLE CalendarDay
( DayID INT IDENTITY(1, 1)
, DayDate SMALLDATETIME
, WeekNumber INT
, OrdinalDate VARCHAR(8)
, DateWeekNumber VARCHAR(10) 
, DayNumber INT
, NameOfDay VARCHAR(10) 
)
GO
SET NOCOUNT ON;
DECLARE
@Date SMALLDATETIME;
SET DATEFIRST 1; --assuming start of week is monday
SET @Date = '2010-01-01';
WHILE @Date < '2011-01-01'
BEGIN
INSERT INTO CalendarDay
( DayDate, WeekNumber, OrdinalDate, DateWeekNumber, DayNumber, NameOfDay )
SELECT @Date
, (DATEPART(WK, @Date))
, CAST(DATEPART(YEAR, @Date) as VARCHAR) + '-' + CAST(DATEPART(DY, @Date) as VARCHAR)
, CAST(DATEPART(YEAR, @Date) as VARCHAR) + '-'
+ 'W' + CAST(DATEPART(WK, @Date) as VARCHAR) + '-'
+ CAST(DATEPART(WEEKDAY, @Date) as VARCHAR)
, DATEPART(WEEKDAY, @Date)
, CASE DATEPART(WEEKDAY, @Date)
WHEN 1 THEN 'Monday'
WHEN 2 THEN 'Tuesday'
WHEN 3 THEN 'Wednesday'
WHEN 4 THEN 'Thursday'
WHEN 5 THEN 'Friday'
WHEN 6 THEN 'Saturday'
ELSE 'Sunday' END;
SET @Date = DATEADD(day, 1, @Date);
END
GO

Array example - Crystal

Local Numbervar counter := 1;
Local Stringvar Array taskdates;
Local Datetimevar dates := CurrentDate;
Local Datetimevar finishdate := DateAdd("yyyy",5,CurrentDate);
Local Stringvar returnstring;

Do
(
//set array size to counter, initally 1, preserving previous size and values
Redim Preserve taskdates[counter];
//assign dates value, initially CurrentDate to array element numbered counter, initially 1
taskdates[counter] := ToText(dates, "dd-MMM-yyyy");
//increment date variable by 1 year
dates := DateAdd("yyyy",1,dates);
//increment counter by 1
counter := counter+1;
)
//continue do loop while date variable is less than or equal to finishdate
While dates <= finishdate ;

returnstring := Join(taskdates, Chr(13))

DateAdd Function - SSRS

=DateAdd(DateInterval.Month, 6, Today())
=DateAdd(”D”, 6, Today())
=DateAdd(”Month”, 1, Today())