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The references here specifically refer to the database column, not derived physical column definitions. All operators and functions may be used in the definition of the physical table column. One special note, in order for this formula to be recognized, the "isExact" property of the physical table column must be set to true. Also note, the referenced physical column must be explicitly defined in the metadata model.
Recent Changes to Physical Table Column Formulas (2009/08/01)
In earlier versions of Pentaho Metadata Editor (post CITRUS), Aggregation aggregation functions needed had to be specified explicitly specified as well as selecting the Aggregation rule. and the aggregation rule had to be selected. This is no longer necessaryrequired, the query that is generated will use the selected aggregation rule when executing. This means you are longer required to designate just one aggregation rule in the model. You can designate multiple aggregation rules from which users can choose when they are working in the Chart Designer or other tool.
Note: This feature will not be supported for users of Ad Hoc Reporting.
In the example below, the model designer has designated three aggregation rules for Priceeach: Sum, Average, and Count. In the Chart Designer, (or other tool), users can decide whether they want to see the total price, average price, or the number of prices available.
Multi-table expressions: Formulas can use any business column in the model
Since the latest versions (after 2008/03/14) it is possible to define formulas that use business columns from anywhere in the business model.
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