• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 193
  • Last Modified:

Report Comparrison

I have an application where I load 2 reports from a database each into its own list view box.

I need to be able to compair the two reports and show the differences found in the 2nd report.

How I show the differences is not important at this time.

What would be the best/most efficient way of doing this?

Should I load each listitem from each listview into the dictionary object and compair them that way?

or would it be better to do an Instr vbCompare while loading the 2nd listview?

I am open to suggestions.

I need what will be the most efficient way as some of the reports can have over 1000 rows.


  • 3
  • 3
  • 2
  • +1
1 Solution
It is better to work with raw data. This is not efficient:
   data >> listview >> collection

This is better:
   data >> listview
   data >> collection (or array)

To find difference, or common elements, see:

"create a common array" (10pts)
contains GetCommon() function

"Comparing listbox contents" (10pts)
contains my GetDiff() function
as i can c there's 2 cases, i am not sure which one is urs
- case1: is that you are looking for differences between the same index from the 2 lists for example:
list1.list(1) should be equal to list2.list(2)
this case is quiet easy:
for p=0 to list1.listcount -1 'assuming that the 2
'lists have the same number of items, or u
'u can write a line to get the max number
if list1.list(p) <> list2.list(p) then
' here you write the code that shows the
'mismatching result
end if
next p
- case2: items r not necessary in the same row.
in this case you should load ur list in a array or use collections as ameba mentioned
raizonAuthor Commented:
its case 2

the two lists are directory scans ex: c:\winnt\system32

The comparrison is to show what has changed
ex.  file not there, modified date, version number, etc.

This is so for example the sys admin can see whats changed on a server since the last report ran after installing a new driver, service pack, software ...etc.

I can load the report into a collection or an array my question then becomes do I concantinate each subitem/field in recordset into a single string then load that into collection/array and compair off of that?

or load it into a multidimentional array?
7 new features that'll make your work life better

It’s our mission to create a product that solves the huge challenges you face at work every day. In case you missed it, here are 7 delightful things we've added recently to monday to make it even more awesome.

I don't know if you checked my samples, but they all use the fact that "collection cannot hold items with the same key."
Take a look at DLSuperC.com.  It has the ability to compare directories quickly and efficiently and has a command line interface.  You could launch the utility and then process the results.

You could use the Windows ?GetFiledata? API to rapidly extract the path and filedatetimestamp from all related directories.  Then you could rapidly do a merge-comparison between the prior snapshot and this one.
raizonAuthor Commented:

looking at your GetDiff() Function.

Looks like this might work or at least get me on the right track.

Will post back tomorrow with further updates.


If you fed the file (with path) and timestamp data into columns in a table in your database, you can run three queries that will quickly tell you the difference between the before and after snapshots.

Query 1 (changed files):
Select A.PathFilename, "Changed On:" + A.DateTimeStamp As
From tblBefore As B Inner Join tblAfter As A ON B.PathFilename = A.PathFilename
Where B.DateTimestamp <> A.DateTimeStamp;

Query 2 (deleted files):
Select B.PathFilename, "Deleted" As Status
From tblBefore As B Left Join tblAfter As A ON B.PathFilename = A.PathFilename
Where A.DateTimeStamp Is Null;

Query 3 (added files):
Select A.PathFilename, "Added" As Status
From tblBefore As B Right Join tblAfter As A ON B.PathFilename = A.PathFilename
Where B.DateTimestamp Is Null;

You can Union these three queries to create one report.
raizonAuthor Commented:
Thanks for the help everyone and the ideas.

I'm using a variation of ameba's GetDiff function.
Thank you for the points!
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Keep up with what's happening at Experts Exchange!

Sign up to receive Decoded, a new monthly digest with product updates, feature release info, continuing education opportunities, and more.

  • 3
  • 3
  • 2
  • +1
Tackle projects and never again get stuck behind a technical roadblock.
Join Now