1. A computer readable storage medium, comprising executable instructions to: receive a dynamic query referencing a set of members of an Online Analytic Processing (OLAP) hierarchy, wherein the dynamic query is evaluated at query execution time; parse the dynamic query into a syntax tree by inserting set functions and set operations into nodes of the syntax tree; receive changes to the OLAP hierarchy metadata indicative of an added calculation; refine the syntax tree in response to the changes; and evaluate the dynamic query to return results that are independent of the changes, such that the dynamic query produces the same results as a static query that is evaluated at set definition time, wherein the executable instructions to evaluate include executable instructions to remove the added calculation.