2 Replies Latest reply on Nov 16, 2012 1:21 PM by 931546

    Creating Dimensions

      Hello, I am a newbie to DW and I am asking for some clarifications.
      I am in the stage of creating Levels, Dim attributes, Level attributes and Hierarchies
      for the dimensions.
      My question is whether I use the excisting fields of my database tables
      for all these or I create new ones. If you could please clarify me for each of them because
      I haven't understand exactly. Your help would be essential to me. Thank you.
        • 1. Re: Creating Dimensions
          nasar.ali-khan at -Oracle
          Generally it is better to create SQL views on top of your tables and then "map" those sql views to olap dimensions and cubes in AWM.

          This will give you additional join and filter abilities, which are often needed when dimensional and cube data moves from relational to olap.

          For each hierarchy, you will create one sql view
          and for each cube you will create one sql view.

          After you have defined all the structures in AWM then goto "Mapping" option for each dimension and each cube
          and you will see the olap objects that need to be populated for that dimension or cube.

          Define your hierarchy sql views and cube sql views, ensuring that all sql columns are present in those sql views which can then be "mapped" to those olap objects.
          • 2. Re: Creating Dimensions
            I am working on Warehouse Builder. I've installed Oracle 11gR2 Entrprise Edition. I see AWM for first time here.

            I've understand that your solution is more effective.
            I am reading a guiding book so I do what it is written. I do not want to 'change any direction',
            because I will be confused.

            My source tables are in an excel file. Can you just tell me if I use any fields from my source data
            to create all these (dim attributes, levels, level attributes, hierarchies) or not?
            I need a more theoretical help first. Thanks again.