3 Replies Latest reply: Sep 23, 2014 11:00 AM by Friedrich Hofmann RSS

    Updating existing data

      I'm just starting out with Qlik and transitioning from Tableau. So, some concepts are familiar, but specific functions are still a little fuzzy.

       

      One important question I have is regarding updating existing data.

       

      The data I'll be analyzing (in QlikSense) will come from static CSV files. The first one I'll get will have about a year's worth of transactions. The company wants to then just give me a new CSV each week with only that current week's new transactions. This data would be added to the existing data (from the previous year) so I'd have one year plus current week. Is there a way to actually manage this with CSV files or do I need a direct database connection?

       

      Thanks,

      JMR

        • Re: Updating existing data
          Friedrich Hofmann

          Hi Jonathan,

           

          I came the same way, from another system. Most things are similar, some are different or new.

          You can of course load all existing .csv files and concatenate (append) them to one another if their structure is always the same - you can do that in a loop or with a Wildcard_LOAD;

           

          Or you can just load what you have (the 1st time round, then save it in a qvd_file.

          => From the 2nd time on, you would first load the qvd, then concatenate the new csv_file and save the end_result.

          => loading from a qvd_file is faster, so this would be preferable c.p.

           

          HTH

           

          Best regards,

           

          DataNibbler

            • Re: Updating existing data

              Thanks...do you have a simple example of a concatenate script that would work for this? Also, do I do this as I first import the data or after it's imported? Again, not sure how Qlik works opposite Tableau.

                • Re: Updating existing data
                  Friedrich Hofmann


                  Hi,

                   

                  sure.

                  For the scenario with a qvd file, you would

                  - The first time round

                    - Load the csv_file(s) into QlikView just as before

                    - use the STORE command to save it in qvd format (check if it's there)

                  - The second time round (and every time from then)

                    - LOAD everything from the qvd_file into QlikView

                    - LOAD the new csv_file (if the structure is always the same, it should be appended automatically; Just check

                       the number of records and the nr. of tables in the data_model (Ctrl+T))

                    - use the STORE command (like before), the existing qvd will be overwritten by the new, slightly bigger one

                  HTH

                   

                  Best regards,

                   

                  DataNibbler