Get all dates between two dates in SQL Server

Question

How to get all 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 dates 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?

Answer 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;