Database Reference
In-Depth Information
Table 12.2 Examples of resource streams and their CWM representations
Resource stream
CWM package of physical model
Class of package
MiningArrayStream
Object-oriented
(i.e.,
Core
)
Package
MiningFileStream
Record
RecordFile
MiningSqlStream
Relational
Catalog
MultidimensionalStream
Multidimensional
Schema
Management
Warehouse Process
Warehouse Operation
Transformation
OLAP
Data
Mining
Business
Nomenclature
Information
Visualization
Analysis
Resource
Relational
Record
Multidimensional
XML
Business
Information
Data
Types
Software
Deployment
Key
Indexes
Expres
sions
Type
Mapping
Foundation
Object
Core
Behavioral
Relationships
Instance
Fig. 12.8 CWM packages used in XELOPES transformations
We mention that each mining input stream contains a method
getLogicalModel
which returns its logical model, i.e., the metadata, and a method
getPhysicalModel
which returns its physical model in terms of a CWM resource packages. The
physical models for some typical resource streams are listed in Table
12.2
. The last
column contains the CWM class that is returned as physical model.
In summary, the mining input stream concept makes XELOPES independent of
physical data sources. Each mining algorithm takes a
MiningInputStream
as input,
probably requests the supported data access methods, and accesses the stream data
through the (supported) standard access methods. The physical stream model, i.e.,
the subclass of
MiningInputStream
passed to the algorithm, is in general not
required to be known by a XELOPES mining algorithm.
12.1.2.4 Transformations
We have introduced the basis and vector classes of the attribute space. Next, the
transformations of bases and vectors will be discussed. Transformations are a
central part of XELOPES Fig.
12.8
.
There are two basic types of transformations supported:
• Transformations of mining vectors
• Transformations of mining input streams
