Chapter 6 Working with PDMs
The mapping for a fact is used to supply data for the cube measures in OLAP databases. You can identify the tables or views used to populate OLAP cubes. The tables in the data source need not be of fact type. Once the source tables or views are identified, you can define mappings between fact measures and table columns.
You have to use the Mapping tab of a fact property sheet to define fact mappings. It contains the following sub-tabs:
The Fact Sources sub-tab allows you to associate one or several tables or views in the data source to the current fact. Data from the selected tables will be transferred to the current fact.
You can use the Add Objects tool to select tables or views from the physical data models open in the current workspace.
For more information about the Add Objects tool, see the "Mapping Editor" chapter in the General Features Guide.
The Measures Mapping sub-tab allows you to define the mapping between measures and columns in the source tables or views.
For more information about the different tools in the toolbar, see the "Mapping Editor" chapter in the General Features Guide.
The Criteria sub-tab allows you to specify join criteria between source tables and dimensions. For example: EMPLOYEE.ID < 100
The Select sub-tab displays the entire SQL statement used to select data in the data source. This statement is automatically generated.
If you modify it, the statement is no longer calculated and the User Defined tool is pressed in the toolbar. You can recover the automatically generated statement by clicking the User-Defined tool, this will automatically remove any non calculated expression in the tab.
The Generate Cube Data feature uses this SQL statement to fill the text files used to populate cubes in an OLAP database.
For more information on the generation of cube data, see section Generating Cube Data.
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