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In earlier versions of Pentaho Metadata Editor, 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. You are no 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
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