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问题:
How to get the dates between two dates?
I have a variable @MAXDATE
which is storing the maximum date from the table. Now I want to get the all dates between @Maxdate
and GETDATE()
and want to store these date in a cursor.
So far I have done as follows:
;with GetDates As
(
select DATEADD(day,1,@maxDate) as TheDate
UNION ALL
select DATEADD(day,1, TheDate) from GetDates
where TheDate < GETDATE()
)
This is working perfectly but when I am trying to store these values in a cursor
SET @DateCurSor=CURSOR FOR
SELECT TheDate
FROM GetDates
Compilation Error
Incorrect syntax near the keyword 'SET'.
How to solve this.
Thanks in advance
回答1:
My first suggestion would be use your calendar table, if you don't have one, then create one. They are very useful. Your query is then as simple as:
DECLARE @MinDate DATE = '20140101',
@MaxDate DATE = '20140106';
SELECT Date
FROM dbo.Calendar
WHERE Date >= @MinDate
AND Date < @MaxDate;
If you don't want to, or can't create a calendar table you can still do this on the fly without a recursive CTE:
DECLARE @MinDate DATE = '20140101',
@MaxDate DATE = '20140106';
SELECT TOP (DATEDIFF(DAY, @MinDate, @MaxDate) + 1)
Date = DATEADD(DAY, ROW_NUMBER() OVER(ORDER BY a.object_id) - 1, @MinDate)
FROM sys.all_objects a
CROSS JOIN sys.all_objects b;
For further reading on this see:
- Generate a set or sequence without loops – part 1
- Generate a set or sequence without loops – part 2
- Generate a set or sequence without loops – part 3
With regard to then using this sequence of dates in a cursor, I would really recommend you find another way. There is usually a set based alternative that will perform much better.
So with your data:
date | it_cd | qty
24-04-14 | i-1 | 10
26-04-14 | i-1 | 20
To get the quantity on 28-04-2014 (which I gather is your requirement), you don't actually need any of the above, you can simply use:
SELECT TOP 1 date, it_cd, qty
FROM T
WHERE it_cd = 'i-1'
AND Date <= '20140428'
ORDER BY Date DESC;
If you don't want it for a particular item:
SELECT date, it_cd, qty
FROM ( SELECT date,
it_cd,
qty,
RowNumber = ROW_NUMBER() OVER(PARTITION BY ic_id
ORDER BY date DESC)
FROM T
WHERE Date <= '20140428'
) T
WHERE RowNumber = 1;
回答2:
You can use this script to find dates between two dates. Reference taken from this Article:
DECLARE @StartDateTime DATETIME
DECLARE @EndDateTime DATETIME
SET @StartDateTime = '2015-01-01'
SET @EndDateTime = '2015-01-12';
WITH DateRange(DateData) AS
(
SELECT @StartDateTime as Date
UNION ALL
SELECT DATEADD(d,1,DateData)
FROM DateRange
WHERE DateData < @EndDateTime
)
SELECT DateData
FROM DateRange
OPTION (MAXRECURSION 0)
GO
回答3:
Easily create a Table Value Function that will return a table with all dates.
Input dates as string
You can customize the date in the the format you like '01/01/2017' or '01-01-2017' in string formats (103,126 ...)
Try this
CREATE FUNCTION [dbo].[DateRange_To_Table] ( @minDate_Str NVARCHAR(30), @maxDate_Str NVARCHAR(30))
RETURNS @Result TABLE(DateString NVARCHAR(30) NOT NULL, DateNameString NVARCHAR(30) NOT NULL)
AS
begin
DECLARE @minDate DATETIME, @maxDate DATETIME
SET @minDate = CONVERT(Datetime, @minDate_Str,103)
SET @maxDate = CONVERT(Datetime, @maxDate_Str,103)
INSERT INTO @Result(DateString, DateNameString )
SELECT CONVERT(NVARCHAR(10),@minDate,103), CONVERT(NVARCHAR(30),DATENAME(dw,@minDate))
WHILE @maxDate > @minDate
BEGIN
SET @minDate = (SELECT DATEADD(dd,1,@minDate))
INSERT INTO @Result(DateString, DateNameString )
SELECT CONVERT(NVARCHAR(10),@minDate,103), CONVERT(NVARCHAR(30),DATENAME(dw,@minDate))
END
return
end
To execute the function do this:
SELECT * FROM dbo.DateRange_To_Table ('01/01/2017','31/01/2017')
The output will be
01/01/2017 Sunday
02/01/2017 Monday
03/01/2017 Tuesday
04/01/2017 Wednesday
05/01/2017 Thursday
06/01/2017 Friday
07/01/2017 Saturday
08/01/2017 Sunday
09/01/2017 Monday
10/01/2017 Tuesday
11/01/2017 Wednesday
12/01/2017 Thursday
13/01/2017 Friday
14/01/2017 Saturday
15/01/2017 Sunday
16/01/2017 Monday
17/01/2017 Tuesday
18/01/2017 Wednesday
19/01/2017 Thursday
20/01/2017 Friday
21/01/2017 Saturday
22/01/2017 Sunday
23/01/2017 Monday
24/01/2017 Tuesday
25/01/2017 Wednesday
26/01/2017 Thursday
27/01/2017 Friday
28/01/2017 Saturday
29/01/2017 Sunday
30/01/2017 Monday
31/01/2017 Tuesday
回答4:
create procedure [dbo].[p_display_dates](@startdate datetime,@enddate datetime)
as
begin
declare @mxdate datetime
declare @indate datetime
create table #daterange (dater datetime)
insert into #daterange values (@startdate)
set @mxdate = (select MAX(dater) from #daterange)
while @mxdate < @enddate
begin
set @indate = dateadd(day,1,@mxdate)
insert into #daterange values (@indate)
set @mxdate = (select MAX(dater) from #daterange)
end
select * from #daterange
end
回答5:
Just saying...here is a more simple approach to this:
declare @sdate date = '2017-06-25'
, @edate date = '2017-07-24'
; with dates_CTE (date) as (
select @sdate
Union ALL
select DATEADD(day, 1, date)
from dates_CTE
where date < @edate
) select
*
from dates_CTE
回答6:
I listed dates of 2 Weeks later. You can use variable @period OR function datediff(dd, @date_start, @date_end)
declare @period INT, @date_start datetime, @date_end datetime, @i int;
set @period = 14
set @date_start = convert(date,DATEADD(D, -@period, curent_timestamp))
set @date_end = convert(date,current_timestamp)
set @i = 1
create table #datesList(dts datetime)
insert into #datesList values (@date_start)
while @i <= @period
Begin
insert into #datesList values (dateadd(d,@i,@date_start))
set @i = @i + 1
end
select cast(dts as DATE) from #datesList
Drop Table #datesList
回答7:
This is the method that I would use.
DECLARE
@DateFrom DATETIME = GETDATE(),
@DateTo DATETIME = DATEADD(HOUR, -1, GETDATE() + 2); -- Add 2 days and minus one hour
-- Dates spaced a day apart
WITH MyDates (MyDate)
AS (
SELECT @DateFrom
UNION ALL
SELECT DATEADD(DAY, 1, MyDate)
FROM MyDates
WHERE MyDate < @DateTo
)
SELECT
MyDates.MyDate
, CONVERT(DATE, MyDates.MyDate) AS [MyDate in DATE format]
FROM
MyDates;
Here is a similar example, but this time the dates are spaced one hour apart to further aid understanding of how the query works:
-- Alternative example with dates spaced an hour apart
WITH MyDates (MyDate)
AS (SELECT @DateFrom
UNION ALL
SELECT DATEADD(HOUR, 1, MyDate)
FROM MyDates
WHERE MyDate < @DateTo
)
SELECT
MyDates.MyDate
FROM
MyDates;
As you can see, the query is fast, accurate and versatile.
回答8:
This can be considered as bit tricky way as in my situation, I can't use a CTE table, so decided to join with "sys.all_objects" and then created row numbers and added that to start date till it reached the end date.
See the code below where I generated all dates in Jul 2018. Replace hard coded dates with your own variables(tested in SQL Server 2016):
select top (datediff(dd, '2018-06-30', '2018-07-31')) ROW_NUMBER()
over(order by a.name) as SiNo,
Dateadd(dd, ROW_NUMBER() over(order by a.name) , '2018-06-30') as Dt from sys.all_objects a
回答9:
DECLARE @FirstDate DATE = '2018-01-01'
DECLARE @LastDate Date = '2018-12-31'
DECLARE @tbl TABLE(ID INT IDENTITY(1,1) PRIMARY KEY,CurrDate date)
INSERT @tbl VALUES( @FirstDate)
WHILE @FirstDate < @LastDate
BEGIN
SET @FirstDate = DATEADD( day,1, @FirstDate)
INSERT @tbl VALUES( @FirstDate)
END
INSERT @tbl VALUES( @LastDate)
SELECT * FROM @tbl