cubes are created using transformer.cubes can be viewed using powerplay.cubes has impromptu query definition (IQD) files as their sources.IQD files are generated from cognos impromptu.IQD files contain ,how the data has to be retrieved through catalogs and logical databases.
To create a cube..
1) save the impromtu report as IQD file.(.IQD)
2)open transformer,go to file-new-ModelName(user defined)-datasourcename(DWH name),source type(select impromptu query definition)-local data file(browse the IQD file save earlier)-check the auto design check box-clk finish-database logon wizard will be opened-enter userid and pwd to connect to the DB---clk log on---A new model will be generated with Dimensionmap,Datasource,Measures,powercube(still cube is not created) and Logical DB(imported from IQD file).
If you select "Run Autodesign" option duting the NEWMODELWIZARD, transformer automatically creates a dimension map and a list of measures for you.even though transformer analyzes the data before creating a dimension map and list of measures,many a time they may not be totally accurate.
To avoid this we need to create Dimensions manually.
3) Now create new Dimensions in the dimensionmap area as per the requirement.select Dimension Map--insert Dimension--name the dimension--Drag and drop columns one below the other from data source(see that the columns are in a hierarchy,Bcoz cubes will be created on these columns with all the possibilities to facilitate drilling,slicing and dicing operations)..check the diagram ,it is displayed empty..data will be shown once the cube is created..
4) go to "Run" and clk on create powercubes.Cube will be created.check the power cube area in the Model.you will observe a cube in that area.This cube can be viewed in Poweplay.
This is one method of creating cube by using IQD file.
The another method of creating cube is my creating a MODEL from Architect and generating a CUBE from that MODEL.