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Enabling Access to Federated Grid
Databases
An OGSA-DAI ODBC Driver
Michael J. Jackson1 Ashley D. Lloyd2 Terence M. Sloan1
1EPCC
2Curtin
Business School &
Edinburgh University Management School
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Overview
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Why develop an OGSA-DAI ODBC driver?
ODBC
OGSA-DAI
Design and Development
What does an OGSA-DAI ODBC driver give us?
Issues and Concerns
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Why?
Facilitate use of standard data analysis tools in a
Grid environment:
– Remove need for Grid awareness
– Allow use of existing data analysis skills in a Grid environment
– Improve rate of adoption of Grid technologies
Data analysis tools:
– SPSS, SAS
How can standard data analysis tools access
Grid-enabled databases?
– An ODBC driver for OGSA-DAI
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Open DataBase
Connectivity – ODBC
ODBC data source
ODBC API
ODBC API
Driver
Manager
Application
Database
API
Driver
Database
Data source
name
Reside on same host
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ODBC Advantages
Application developers:
–
–
–
–
Applications can be database-independent
No need to compile against database-specific libraries
Call-level interface – execute SQL generated at run-time
Change a database => only change driver and configuration
Database manufacturers:
– An ODBC-compliant driver allows the database to be a back end
for any ODBC-compliant application
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OGSA-DAI
 Open Grid Services Architecture – Data Access and
Integration:
– Extensible framework for data access and integration
– Expose heterogeneous data resources to a Grid through web services
 Data operations:
– Access, update, management and integration – relational, XML, files
– Compression and transformation
– Delivery to URLs, FTP, GridFTP, mail, other services
 Base for developing higher-level services:
– Data federation and distributed query processing
– Data mining
– Data visualisation
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Accessing Data Resources
via OGSA-DAI
OGSA-DAI
Perform
document
Application
OGSA-DAI
Data
Service
JDBC
API
Database
OGSA-DAI
Response
document
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An ODBC Driver for
OGSA-DAI
ODBC API
ODBC API
Driver
Manager
Application
Data source
name
Driver
OGSA-DAI
Perform
document
OGSA-DAI
Response
document
OGSA-DAI
Data
Service
JDBC
API
Database
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A Simple Scenario
Data analysis
ODBC view:
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Connect to OGSA-DAI ODBC data source
Submit a SELECT * FROM table query
Get back the results
Disconnect from the data source
OGSA-DAI view:
–
–
–
–
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Connect to an OGSA-DAI data service
Construct a Perform document holding the query
Send it to the service
Receive a Response document from the service
Parse it to get the results
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Development Options
Implement an OGSA-DAI ODBC driver:
– From scratch
Use an open source ODBC driver:
– Extract a data resource-independent skeleton
– Customise it to OGSA-DAI
Use an ODBC SDK:
– OpenAccess
– Simba
– Syware
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Using an SDK
Proof of concept:
– Prototype within a tight time-scale
OpenAccess SDK:
–
–
–
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30 day evaluation licence
Provides an ODBC driver
Developer codes an Interface Provider (IP)
Supports Java development => exploit OGSA-DAI’s client toolkit
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An ODBC Driver for
OGSA-DAI using OpenAccess
OGSA-DAI
CTk API
OpenAccess
API
OpenAccess
ODBC Driver
Interface
Provider
Data resource
configuration
(e.g. service
URL)
OGSA-DAI
Client
Toolkit
OGSA-DAI
Perform
document
OGSA-DAI
Data
Service
OGSA-DAI
Response
document
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Testing
OpenAccess ODBC SQL query tool:
– Submit SQL statements to an ODBC data source
– Present the results
EPCC:
– OGSA-DAI ODBC data source on a PC
– ODBC driver + OGSA-DAI service URL
Curtin Business School:
– OGSA-DAI server and services
– Database
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What does this give us?
Transparency:
– Database location
• Changes are restricted to the OGSA-DAI server
• Client applications are unaffected
– Database product
Global access of data:
– Publish service URL
Security:
– Database user names and passwords reside on OGSA-DAI
server
– Clients can be required to provide credentials to connect to
OGSA-DAI services
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Data Federation
ODBC API
ODBC API
Driver
Manager
Application
Data source
name
Driver
OGSA-DAI
documents
OGSA-DAI
Data
Service
Virtual database
Database Database Database
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Issues and Concerns
OGSA-DAI WSI / WSRF compliance:
– Prototype developed using OGSA-DAI OGSI
– Data source includes OGSA-DAI factory service URL
– OGSA-DAI WSI or WSRF – data service URL + resource ID
Driver development:
– Complete the OpenAccess IP
– Write a pure OGSA-DAI ODBC driver from scratch
ODBC conformance
– Cursors, sessions, transactions, timeouts, meta-data
– Analysis of SAS or SPSS ODBC usage
Efficiency
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Questions
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