Patent ID: 9135302
Filing Date: 2015-09-15
Classification: G06F

Abstract:
1. A computer-implemented method, comprising steps of: selecting, from among a hierarchy of materialized views, only first-tier materialized views that depend directly on a base table; establishing a set of candidate materialized views that consists only of the first-tier materialized views; based on a cardinality of a nested materialized view that is a descendant of a particular first-tier materialized view, selecting the particular first-tier materialized view from among the set of candidate materialized views even though the particular first-tier materialized view does not have a lowest cardinality among cardinalities of first-tier materialized views in said set of candidate materialized views; based on said selecting, rewriting an existing query statement, which references said base table, into a rewritten query statement that references said particular first-tier materialized view instead of said base table; wherein said first-tier materialized view is a parent materialized view to another materialized view; and wherein said method is performed by one or more computing devices.