Defines a set of measures known at the same level of granularity. All the measures of a MeasureGroup must be sourced from a single table.
type MeasureGroup =
A MeasureGroup is bound to a table in a data source view; and each measure is bound to a column in that table. Finally, each measure group dimension has a set of 'granularity attributes', which define the granularity of the MeasureGroup.