Question

I have a table::

ItemID  VersionNo  CreatedDate
-------------------------------
1       3          7/9/2010
1       2          7/3/2010
1       1          5/3/2010
1       0          3/3/2010
2       0          4/4/2010
3       1          4/5/2010
3       0          3/4/2010

…where Version 0 means .. its a newly produced item. Here I need to find time,(time gap between two versions) and add a column as process time.
like::

ItemID  VersionNo  CreatedDate  ProcessTime
-------------------------------------------
1       3          7/9/2010     6Days or 6*24Hrs
1       2          7/3/2010     60Days 
1       1          5/3/2010     2Days
1       0          3/3/2010     ''
2       0          4/4/2010     '' 
3       1          4/5/2010     31Days
3       0          3/4/2010     ''

VersionNo’s are not Fixed..means with time, it could increase… How to acheive the desire result in MS Access or in SQL-Server.

Thanks in advance for all your sincere efforts.
Thanks

Answer 1

How about (Access):

SELECT t.ItemID, 
       t.VersionNo, 
       t.CreatedDate, (
          SELECT Top 1 
          CreatedDate 
          FROM Versions v 
          WHERE v.ItemID=t.ItemID 
          And v.VersionNo<t.VersionNo 
          ORDER BY VersionNo DESC) AS LastDate, 
       DateDiff("h",[LastDate],[CreatedDate]) AS DiffHrs,
       DateDiff("d",[LastDate],[CreatedDate]) AS DiffDays
FROM Versions t