2 Replies Latest reply: Jun 12, 2012 4:00 AM by hannesse RSS

    Study how field values changes over time

      Hello.

       

      I have a Oracle database that contains some fields that can change value over time.

      Is it possible with QlikView to design a script that somehow stores this changes so you later can study this changes.

      I.e look at a particular field and see that this field had the value false last week but two days ago it changed to true?

       

      Hope you understand what I mean!

       

      Thank you in advance!

       

      /Hannes

        • Re: Study how field values changes over time
          Christophe Brault

          Hi,

           

          If i well understodd what you want to do, yes I think its possible. To verify if the value changes overtime, you need to write the timestamp when you check it.

           

          A solution could be to store historical values in a QVD.

           

          Example of script :

           

          The first time you create the QVD :

           

          TABLENAME:

          SELECT your chain connection...

           

          YourField, now() as Date

          ...;

           

          store TABLENAME into QVDNAME.qvd;

           

          When created, clear your script and then use something like this :

           

          TABLENAME:

          load * from QVDNAME.qvd;

           

          concatenate

          SELECT your chain connection...

           

          YourField, now() as Date

          ...;

          store TABLENAME into QVDNAME.qvd;

           

          This script will load you past data and meet them with the last reload values and store all in a new qvd. Each time you will reload, the QVD add a line to your data.

           

          Hope this meet your needs.

            • Re: Study how field values changes over time

              Okay, I think i understand, I have managed to design a normal incremental script already so I'll take a look at this!

              Do you think that this i a good idea since I think that a reload will be made each night? Maybe you can design the script so that it only loads the field that actually has changed? If im not mistaken you script above looks like it loads all values?

               

              Thank you in advance!

               

              /Hannes