If you have not yet introduced yourself to the basic concepts of flex.bi then please start with an overview of flex.bi concepts and learn how to analyse and create reports. This tutorial will explain how to define new calculated members using MDX calculation formulas.
If you have never worked with MDX before, we suggest you watch this video: MDX basic concepts
Dimensions and hierarchies
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Each dimension typically will have a default All member which can be used to get totals of measures per this dimension. If the Customers dimension has a default All member named a All Customers then you can reference it with [Customers].[All Customers]. Since the default All member can be renamed it is safer to use [Customers].[DefaultMember] to to get the same result. The time dimension has two default All members for each hierarchy - [Time].[DefaultMember] and and [Time].[Weekly].DefaultMember.
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