DAX Tabular specifics

AtScale now supports exposing a multi-dimensional model through a Tabular DAX interface. This feature enables Power BI Tabular users to avoid re-modeling hierarchies and attributes that already exist in an AtScale model, while simultaneously allowing report authors to create client-side measure expressions.

This method of accessing AtScale represents a new hybrid access model that promotes centralized control of dimensions and facts, and distributed control of report-scoped expressions. Because AtScale exposes a model and not raw tables, you should keep in mind the principles listed in the sections below.

Relationships

Relationships are created in the AtScale model and not in the Power BI Tabular model. As a result, Relationship functions are not applicable when making Tabular connections to an AtScale Model.

Access to row-level table data

Report Authors do not have direct access to row-level table data. Report authors can access data down to the lowest server-side dimension level defined by the AtScale Model architect.

Overriding aggregation functions

Report authors cannot override aggregation functions that are part of server-side Measure definitions. If a report author attempts to re-aggregate a Measure, AtScale will ignore the inbound aggregation function and will use the server-side aggregation function specified in the Measure's definition.

Referencing columns and tables

DAX functions that reference "Columns" should reference AtScale Levels or Attribute Names. DAX functions that reference "Tables" (such as ALL()) should instead reference AtScale "Hierarchies".

For example, the "Color" attribute of the "Product" dimension is referenced in the server-side AtScale MDX language using the fully qualified syntax [Dimension].[Hierarchy].[Level]. Since "Color" is an attribute and not a hierarchy level, the reference degenerates to [Product].[Color].[Color] in the server-side language. In a PowerBI Tabular expression, use the "Hierarchy" component, "Color" in this case. For example, to create an expression that shows the [Internet Sales Amount Local] measure for Products where "Color" = Red: :

[SalesForRedProducts] = CALCULATE([Internet Sales Amount Local],'Product'[Color] = "Red")

IntelliSense suggestions

Ignore PowerBI's IntelliSense suggestions to pick Attribute Key or Sort Key properties as selections for Table or Column parameters DAX functions.