MAINTAINING PRE-COMPUTED AGGREGATE VIEWS INCREMENTALLY IN THE PRESENCE OF NON-MINIMAL CHANGES

摘要

Methods and apparatus implementing a technique for incrementally maintaining pre-computed aggregate views. In general, the technique includes: receiving a pre-computed aggregate view derived from one or more base tables. The pre-computed aggregate view including a pre-computed aggregate table and a view definition. The view definition including aggregation functions that can be any combination of sum, sum distinct, count(*), count distinct, min, and max. The view definition further including expression that may be nullable. The technique includes receiving changes to the base table, the changes being non-minimal. The technique includes receiving changes to the base table, the changes being non-minimal. The technique includes analyzing the view definition, including type of aggregation functions and the nullability and data type of columns and expression in the view definition, to reduce or eliminate the use of information in base tables in order to define the incremental modifications to the pre-computed aggregate table.