An expression that uses an InterSystems MDX extension to refer to a hierarchy in another cube, via the following syntax:
Where relationship_name is the name of a relationship in the cube used by the query and hierarchy_expression refers to a hierarchy contained in that relationship.
A bare hierarchy expression returns all records; this expression is equivalent to an All member. (Note that you can use a bare hierarchy expression even if the dimension does not formally define an All level.) For example:
SELECT MEASURES.[%count] ON 0, colord.h1 ON 1 FROM patients
Also, you can use a hierarchy expression as an argument to any of the following functions: