3 Replies Latest reply: Aug 4, 2016 3:57 AM by inbar kipnis RSS

    qvds loses data when service crashes



      I have a problem with reliability of data in the qlikview models. I found that whenever the server crashes or one of the services crashes, the qvds have less data than before the crush. The qvds actually loses rows of data. This issue is critical, because it hurts the credibility of the models.

      I load my data incremental, so it can't recover itself when in reload.

      Any solution for this?

        • Re: qvds loses data when service crashes
          Gysbert Wassenaar

          Backup your data so that a system crash that causes corruption of the file system does not result in permanent data loss.

          • Re: qvds loses data when service crashes
            Colin Albert

            Perhaps you need to design an overlap into your incremental load.

            Load the from the source database for the past N days, months or hours, and then append data from the stored QVD using a where not exists clause to prevent duplicate data. Finally re-write the updated qvd.


            I assume the QVD corruption is caused by the server crash occurring during the re-write of the qvd.


            I would also consider investigating the cause of the server crash and resolving the issue, as from the wording of your question this seems to be a regular occurrence!

            • Re: qvds loses data when service crashes

              My issue resolved by qlikview tech help.

              The server crushes and the data lose were related to each other. apparently when the memory reached it's limit of 90% the qvds were stored partially because there was not enough memory to complete the save, and the server restarted itself to clear the cashe memory.

              So the solution is:

              1. Remove all preloads so it won't stay in the memory.

              2. Clear cash every night by adding the row ClearCacheTimesPerDay=1 to the settings.ini file