3 Replies Latest reply: Feb 26, 2014 1:21 AM by Mohit Sharma RSS

    How to Optimize our QV application ?

    Helen Betty

      Thanks

      Helen

        • Re: How to Optimize our QV application ?
          sivasankar kanagasabai

          Helen,

          Qlikview Optimization can be done at many levels. Find the attached document for brief explanation with examples.

          Regards.

          Sivasankar k

          • Re: How to Optimize our QV application ?
            sujeet singh

            Go this PDF i have placed at community

             

            http://community.qlik.com/docs/DOC-4556

            • Re: How to Optimize our QV application ?
              Mohit Sharma

              When you fetching data from data source and store it into qvd then again load that data from qvd and without filter it reload the qvd meaning optimizing

              here look it

              1. 1)      Optimized and unoptimized QVD Load Situations?
              2. Ans. When concatenating two tables that don't have the same number of fields, if the second table has the same fields than the first one and then some extra fields the load will still be optimized, if done the other way around it will not be optimized.

              e.g. All Loads are optimized

              Table:

              LOAD // Optimized

                   A,

                   B,

                   C

              FROM Table1.qvd (qvd);

              CONCATENATE(Table) // Optimized

              LOAD

                   A,

                   B,

                   C,

                   D,

                   E

              FROM Table2.qvd (qvd);

              e.g. 2nd Load isn't optimized

              Table:

              LOAD // Optimized

                   A,

                   B,

                   C,

                   D,

                   E

              FROM Table2.qvd (qvd);

              CONCATENATE(Table) // Not optimized

              LOAD

                   A,

                   B,

                   C

              FROM Table1.qvd (qvd);

                   Or   2nd Ans. Is

              Optimized load is much faster and therefore preferable, especially for larger data sets.

              Optimized loads are possible if no transformations (calculations) are made during the load, and no (almost) filtering is done in a WHERE clause.

              The only acceptable filter is using function Exists:

              WHERE Exists(Field)

              So for example this load can't be optimized:

              Load * From ... WHERE Country = 'US'

              but this load can:

              Load * From ... WHERE EXISTS(Country)

              ================================

              On the other hand, the only time you want the load not to be optimized, is if you load a Mapping table from a QVD file. In this case, Optimized load doesn't quite work, so you want to make the load non-optimized deliberately.

              Another Answer For Optimize and Non- Optimized

              Optimized load is much faster and therefore preferable, especially for larger data sets.

              Optimized loads are possible if no transformations (calculations) are made during the load, and no (almost) filtering is done in a WHERE clause.

              The only acceptable filter is using function Exists:

              WHERE Exists(Field)

              So for example this load can't be optimized:

              Load * From ... WHERE Country = 'US'

              but this load can:

              Load * From ... WHERE EXISTS(Country)

              ================================

              On the other hand, the only time you want the load not to be optimized, is if you load a Mapping table from a QVD file. In this case, Optimized load doesn't quite work, so you want to make the load non-optimized deliberately.