qbx: a case tool for data mart design - er 2011...
TRANSCRIPT
www.qbx-tool.com
QBX: A CASE Tool for Data Mart Design
Antonino Battaglia Matteo Golfarelli Stefano Rizzi
University of Bologna - Italy
Rome - Italy
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Motivation
! Data warehouses have become an essential element for strategic analyses
! Data warehouse systems are characterized by a long and expensive development process that hardly meets the requirements of today's market ! This is one of the causes behind the low penetration of data
warehouse systems in small-medium firms, and behind the failure of whole projects
! One of the directions to increase the efficiency of the data warehouse development process is to automate the design of data marts ! Some research prototypes of CASE tools have been
developed ! Commercial tools (such as Oracle Warehouse Builder) are
oriented to a single platform and should be considered as design wizards rather than CASE tools
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Overview
! QBX is a CASE tool resulting from a close collaboration between academy and industry
! It includes two separate components: ! QB-Xpose
• used by designers for conceptual design, logical design, and deployment of ROLAP data marts in the form of star/snowflake schemata
! QB-Xplore • accessed via browser by business users and technical
experts to interactively explore project-related knowledge at different levels of abstraction
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Features
! A basic feature of QBX is that of using conceptual schemata for multidimensional design ! Conceptual modeling provides a high level of abstraction in
describing the multidimensional repository, aimed at achieving independence of implementation issues
! It is recognized to be the necessary foundation for building a data warehouse that is well-documented and fully satisfies user requirements
! It relies on a graphical notation that facilitates writing, understanding, and managing conceptual schemata by both designers and business users
Dimensional Fact Model
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Functionalities
! Conceptual Design ! Automate conceptual design by choosing relevant facts on a
source operational database schema and letting QBX draw your hierarchies (supply-driven approach)
! Or you can create your data mart conceptual schema from scratch by composing existing hierarchies and reusing conformed dimensions (demand-driven approach)
! Logical Design ! QBX translates your data mart conceptual schema into a
logical (star/snowflake) schema following your design preferences and taking your data volume into account
! QBX will then support you in deploying your data mart by generating SQL code for your relational DBMS and writing meta-data onto the Mondrian and Microstrategy OLAP engines
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Functionalities
! Reverse Engineering ! Draw the conceptual schema of an existing data mart
starting from its relational schema ! Data Mart Interoperability
! Import and export your conceptual schemata to OLAP engines
! Project Documentation ! QBX creates the documentation for your data mart, including
fact schemata, conformed dimensions, glossaries, data volumes
! Publish expressive and easy-to-read documentation on the web to be explored and annotated by business users and technical experts
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Forward engineering
CONCEPTUAL DESIGN
LOGICAL DESIGN
Requirements Design Options
Logical Schema Data Volume Operational DB
DEPLOYMENT
OLAP Meta-data
Data Mart
QBXpose
Project Documentation
QBXplore Designer
Technical Expert
Business User
WEB BROWSER
Conceptual Schema Logical Schema
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Reverse engineering
IMPORT
OLAP Meta-data
Data Mart
QBXpose
Project Documentation
QBXplore
Technical Expert
Business User
WEB BROWSER
Conceptual Schema Logical Schema
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Conceptual design
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Logical design