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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
In earlier versions of Pentaho Metadata Editor, (prior to 2009/08/15), aggregation functions had to be specified explicitly and the aggregation rule had to be selected. This is no longer necessary; the query that is generated will use the selected aggregation rule during execution.
Multi-table expressions: Formulas can use any business column in the model
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