Integrated Meta Database IMDB Architecture

1
Integrated Meta Database (IMDB) Architecture

• Open Forum 2003 on Metadata Registries
• 1030 1115
• January 22 2003

Amie Lee, Dave Harrison Statistics Canada
2
Design Goals

• Web deployable (Project/Architectural)
• Acceptable Performance (Project/Architectural)
• Thin-client (Architectural)
• Alleviates burden on client machine
• Faster run and load time, ease of deployment
• n-tier (Architectural)
• Development of corporate components
• Services/products available from multiple vendors
  (Architectural)
• Bilingual (Project, Architectural)

3
Implementation

• Two different architectures
• 1999-2002 Phase 2 - Input of meta information
  for statistical business processes
• 2002- 2003 Phase 3 - Input of meta data for data
  elements
• Phase 2 implementation frozen because of
• Discontinued support for software by vendor
• Size of system has exceeded the capabilities the
  selected web deployment technology.

4
Phase 22-Tier (plump client) Model
Technologies

Tools

Presentation Application (Business Rules)
Internet Explorer Sun Java Plug-In V1.1.3 Swing
1.0.3
Web Browser Java Applet


JDBC
Oracle JDBC Driver
Middleware
Application (Business Rules Data Access
Logic) Data Layer

• Oracle 8i
• Oracle (PL/SQL)

RDBMSwith Stored Procs
5
Phase 2 Bilingualism
Menu items
Tabs
Directive
English and French text fields
Labels
Coded fields
Buttons
6
Phase 2 Bilingualism
Text for elements of the interface
English
Resource Bundle Key Value menu_File File tab_
ID Identification tab_Des Description ...
7
Phase 2 Input Screens
Text strings related to data components
Directives Resource Bundle Key
Value SurveySDDS Statistical Data Doc ...
IMDB database
Labels Resource Bundle Key Value SurveySDDS
SDDS ...
8
Phase 2 Input ScreenAdministered Component
Component type
Title area
Directive area
Administered component tabs
Input Area
9
Phase 2 - Identification Tab
10
Phase 2 - Organization Tab
11
Phase 2 DescriptionTab Statistical Activity
and Survey
12
Factory Pattern applied to Description
Instrument Request
Survey Request
Description Factory
13
Phase 2Model View Controller Pattern

• Model maintains the data
• View displays the data
• Controller event handlers for the Model and
  View
• Phase 2 combines the View and Controller

14
Phase 2Mapping of Relational Model to OO
Visual Age DATA ACCESS BUILDER
IMDB Relational Database
JDBC Class
15
Phase 2 2001 Achievement of design goals

• Web deployable? via Applet however plug-in
  technology was not stable and removed from
  deployment.
• Acceptable Performance? Applet very slow for
  load time. Performance is improved by deployment
  as an application on the client. Support provided
  for both Applet and Application versions.
• Thin-client? Plump client
• n-tier? 2-tier
• Services/products available from multiple
  vendors? No vendor support for Visual Age 3.0
  DAB. Code is not compliant with Java 2.
• Bilingual ? English and French

16
Phase 3 Considerations

• Design Goals
• Conformance with standards.
• Minimize use of auto generation tools/wizards,
  therefore reducing risk of vendor lock-in.

17
Phase 33-Tier (thin client) Model

Tools

Technologies
Presentation Layer
Web Browser
Internet Explorer 6.0

Jdom b8 Xalan-Java 2.4.1 Apache Xerces 2.20

XML 1.0
Application Layer
Jakarta Tomcat 4.1.12 Servlet 2.3
Web Server


JDBC
JDBC
Data Layer
Oracle 8i
RDBMS
18
Phase3MVC - Model
Meta data structure of each container describes
the contents of the container and the host of the
container.
Process XML XML to populate the meta data
structure of the object.
produces
Content XML XML to provide the contents of object
used in a statistical business context.
19
Phase 3 MVC - View
Container Meta data structure
Container data dictionary
Internationalized dictionaries
Content XML
Process XML
XSL transformation
XSS
XHTML
20
Phase 3MVC - Controller
Container Meta data structure
Servlets
21
Phase 3 Bilingualism

• Multi-lingual
• Internationalized dictionaries
• eXstensible Style Sheets

22
Phase 3 2003 Achievement of design goals

• Web deployable? via XML, XSLT
• Acceptable Performance? Lightweight web
  interface
• Thin-client? yes
• n-tier? 3-tier
• Services/products available from multiple
  vendors? Open solution using open software
• Bilingual? Multi-lingual (English is the base
  reference language.)

23
Phase3 Status

• Modeling and design
• Basic implementation
• Login processing
• Container management
• Data input operations

24
For More Information

• Amie Lee, Dave Harrison
• Statistics Canada
• Amie.Lee_at_statcan.ca
• Dave.Harrison_at_statcan.ca