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1EPCC2Curtin Business School &

Edinburgh University Management School

Michael J. Jackson1 Ashley D. Lloyd2 Terence M. Sloan1

Enabling Access to Federated Grid Databases

An OGSA-DAI ODBC Driver

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Overview

• 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

Application Driver Manager

Driver

ODBC data source

Data source name

Database

DatabaseAPIODBC APIODBC API

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

ApplicationOGSA-DAI

Data Service

OGSA-DAI Response document

Database

JDBCAPI

OGSA-DAI Perform

document

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An ODBC Driver for OGSA-DAI

Application Driver Manager

Driver

Data source name

ODBC APIODBC API

OGSA-DAI Data

Service

OGSA-DAI Response document

Database

JDBCAPI

OGSA-DAI Perform

document

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A Simple Scenario

Data analysis ODBC view:

– 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:– 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:– 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

OpenAccess ODBC Driver

Interface Provider

Data resource configuration(e.g. service

URL)

OGSA-DAI CTk APIOpenAccess

APIOGSA-DAI

Data Service

OGSA-DAI Client Toolkit

OGSA-DAI Response document

OGSA-DAI Perform

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

Application Driver Manager

Driver

Data source name

ODBC APIODBC API

OGSA-DAI Data

Service

OGSA-DAIdocuments

DatabaseDatabaseDatabase

Virtual 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