topic Re: Compare 2 QVDs in QlikView

Compare 2 QVDs

Anonymous — Tue, 03 Feb 2015 14:30:27 GMT

Hi Experts,

I want to compare data from 2 qvds and present it in a qvw. Can someone suggest the ideal approach to do this?

Thanks in advance.

Re: Compare 2 QVDs

alexandros17 — Tue, 03 Feb 2015 14:31:52 GMT

What do you mean with compare?

You can load each qvd, but what do you want to do then?

Let me know

Re: Compare 2 QVDs

Anonymous — Tue, 03 Feb 2015 14:39:25 GMT

The 2 qvds are from different environment. (PROD and UAT)

So, I want to do a comparison of data in the front end after loading them.

As of now, I am simply loading data from 2 files, using qualify (as the field names are similar) and then pulling the data in the front end in 2 different straight tables.

Just wanted to know , is there any other ideal approach to do this?

Hope I made myself clear.

Re: Compare 2 QVDs

maleksafa — Tue, 03 Feb 2015 14:48:32 GMT

if you are dealing with numbers, the ideal thing i guess is to load both qvds in different tables or same table but with different flag (to identify them) and then create a statistics box on each set of data and do the comparison.

Re: Compare 2 QVDs

giakoum — Tue, 03 Feb 2015 14:54:02 GMT

embarrassing as it may sound , I use Excel to compare 2 data sets

Just creating a column subtracting the same field from each data set and dragging it across the dimension. if there is a value other than 0, there might be a potential issue.

Re: Compare 2 QVDs

Peter_Cammaert — Tue, 03 Feb 2015 15:17:52 GMT

My initial idea (some years ago when dealing with a problem with Incremental loads of very large tables) was:

Make a QVW document that:

Loads the first version of the QVD and adds a primary key to it
Loads the second version of the QVD and joins it to the first (OUTER JOIN)
Reloads the resulting table and creates flags for all field pairs that differ.
Create a few UI objects with counters for nr of records and a table with counters for field differences.

If you want to do it for all fields, you're in for a lot of work. If you want to do this for a few important fields, or just to count the number of differing records, it is doable.

Re: Compare 2 QVDs

alexandros17 — Tue, 03 Feb 2015 15:43:41 GMT

Clear, but analysis depend on totals, on selections and so on, the best thing would be reading the 2 qvd leaving the key fields with the same name (Unqualify those fields) in order to put them as dimension and add expressions from other fields that sum values

It's an idea, let me know

Re: Compare 2 QVDs

Anonymous — Thu, 05 Feb 2015 11:19:49 GMT

Thank you guys for all the help! 🙂