Compensating for unbalanced hierarchies when generating OLAP queries from report specifications

摘要

Systems, methods and articles of manufacture are disclosed for generating an online analytical processing (OLAP) query against a cube. The cube may have dimensions, each dimension having a hierarchy of members. A report specification may be received against a hierarchy of the cube. An OLAP query may be generated from the report specification. The OLAP query may include projected members not having any descendant at the detail level of the hierarchy, thus producing more accurate results.

主权项

1. A computer-implemented method to provide an online analytical processing (OLAP) query for data aggregated in a cube, the cube having a plurality of dimensions, each of the plurality of dimensions including a hierarchy of members, the computer-implemented method comprising:
receiving a report specification against a hierarchy of the cube; upon determining the report specification satisfies predetermined criteria for additional processing: generating a first OLAP query that includes a compensation operation, the predetermined criteria including: (i) the report specification having a target operation to apply to a lowest level of the hierarchy; and (ii) the report specification projecting a portion of the hierarchy to the exclusion of the lowest level of the hierarchy; in executing the first OLAP query, applying the target operation to a first set of members identified from the hierarchy, the first set consisting of members projected by the report specification that have a descendant disposed at the lowest level of the hierarchy, the target operation to the first set being applied at the lowest level of the hierarchy; performing the compensation operation by applying the target operation by one or more computer processors in order to process a second set of members identified from the hierarchy and distinct from the first set, the second set consisting of members projected by the report specification that do not have any descendant disposed at the lowest level of the hierarchy, the target operation to the second set being applied at a non-lowest level of the hierarchy; and combining the first set with the processed second set via a union operation and in order to produce results responsive to the report specification, whereby the compensation operation prevents the processed second set from being incorrectly omitted from the results; and upon determining that the report specification does not satisfy the predetermined criteria for additional processing:
generating a second OLAP query that does not include the compensation operation; andin executing the second OLAP query, applying the target operation to the first set of members identified from the hierarchy and in order to produce a set of results responsive to the report specification, the target operation to the first set being applied at the lowest level of the hierarchy, whereby the compensation operation is not performed as part of executing the second OLAP query.