Package org.pentaho.aggdes.algorithm


package org.pentaho.aggdes.algorithm
Defines the interface of the Aggregate Designer algorithm and supporting classes.

The Aggregate Designer consists of a number of components:

  • The schema loader component (SchemaLoader) reads a star schema and presents the algorithm with a Schema object and embedded Table and Attribute objects.
  • The algorithm component (Algorithm) tries to find the most efficient set of aggregates for a given schema. A set of aggregates is efficient if it enables any expected query to evaluate quickly yet has a reasonable cost in terms of disk space and load time.
  • The result handler component (org.pentaho.aggdes.output.ResultHandler) converts the result of the algorithm into a useful form such as a script of CREATE TABLE statements to create aggregate tables and INSERT statements to populate them. A result handler is not necessary if you are invoking the algorithm programmatically and your program will process the (Result)object produced by the algorithm itself.

Each of the components is specified a particular Java interface that extends Component. There is a default implementation for each component, but you can provide your own.

There is a command-line utility org.pentaho.aggdes.model.Main to allow you to invoke the algorithm. You can choose which implementation of each component, and provide parameters to each component.