Cube Designer in SQL Server Data Tools (SSDT)/BIDS is used to edit various properties of an existing cube, including the measure groups and measures, cube dimensions and dimension relationships, calculations, key performance indicators (KPIs),
actions, partitions, perspectives, and translations included in the cube, as well as to browse the data contained by the cube.
We recommand you to use Calculation Tools (Calculations Tab, Cube Designer) to access calculation part of cube and modify them. And there is no other tools to achieve this requirement.
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