Care and Feeding of a Data Warehouse

Mary Louise PowersLehigh University

SCT Banner® Technical Environment

All SCT Banner modules installed

All ‘Web for’ products installed

AIX/Unix, Oracle 8i

Maintained by Enterprise Systems (ESI)

Project Background

Request for a data warehouse from Institutional Research (IR)Strategic decision supportTrend analysisEfficiency and accuracySingle institutional data source

Project Background

Warehouse definitionTime slice, Pre-defined eventsStrategic, not transactionalNot a Data Mart for operational reportingDirect / indirect customersData, not reports

Project Scope

Design and implementation from Spring 2001 to Fall 2002Graduation back to 1992Enrollment/Registration from Fall 2001Primary reporting source for IR

Design

Focused on enrolled students, courses, graduation Reporting needsBusiness processesTechnical interest in Dimensional Model and Star Schema

Star Schema

Time_Dimension

PK Time_Key

I4 TermAcademic_Year

I1 Activity_Date..

I3 .I4 .

Instructor_Dimension

PK Instructor_Key

I3 IDDepartmentCollege

I3 ..

I4 .I3 .

Demographic_Dimension

PK Demographic_Key

I4 GenderEthnicity

I3 Age....

Registration_Fact

PK,FK4,I1 Demographic_KeyPK,FK2,I1 Instructor_KeyPK,FK3,I1 Time_KeyPK Course_Key

Course_IDCredit_HoursGrade....

Course_Dimension

PK Course_Key

I5 TermSubject

I6 DepartmentI5 .

.I8 .

.

Design

High level technical designTranslated internal processes into schemaAllowed for implementation of flat tables

Stop gap measureSupporting data from Admissions & Financial Aid

Software RequirementsExtraction, translations, cleansing Loading and warehouse table buildsCreation of summary tables and views

SCT Banner Executive-Self Service (WFE)

Data Warehouse Executive Briefing Center Administrative interface

Production Environment

Three databasesSCT Banner Production“Stage” (copy of SCT Banner Production)

Built from Banner exportProvides “snapshot” of Banner at critical point in time – data is frozenLimited access

Data Warehouse

Production OperationsEnrollment / Registration / Graduation

extracts

Enrollment/Registration Events: 10th day census Midterm censusLast day of classClose of term

Production Operations

Pre-export audit reporting – SCT Banner production

Export of SCT Banner production database

Create Stage database from export (can be refreshed at any point in time)

Production Operations

Pre-extract audit reporting – Stage

Clean up of Stage databaseSynchronize of Stage and Banner correctionsArchive corrected copy of StageAudit trail

Run warehouse maintenance process

Customizations / Enhancements

ChallengesData qualityTime involvementGetting accurate specifications

Post Refresh Process

Administering / ManagingProduction Operations

Manage events processingSCT Luminis 3 Portal – Calendar and task list

OperationsWho runs the warehouse Support and troubleshooting

SecurityRequest Tracking System

Technical

Infrastructure maintenanceSource code housekeepingArchiving processesWFE upgradeOracle upgradesOptimize Stage database creation

Documentation

MetadataPreliminary stageQuest Software - Toad ®

Common Lehigh definitions

Documentation

Work in Progress

You are never doneData retention requirements - TBDData integrity issuesPotential for implementation of other areasChanging business perspectives (New VP’s, etc)

Conclusion

On going challengesComplexity of the system Timing and synchronizationLehigh’s data quality requirements

BenefitsPrimary data source for IREase of use for historical reportingStability of data

References

Adamson, C. & Venerable, M. (1998) Data Warehouse Design Solutions. John Wiley & Sons, Inc.

Dodge, G. & Gorman, T. (1998) Oracle8 Data Warehousing, A Hands on Guide to Designing, Building, and Managing Oracle Data Warehouses. John Wiley & Sons, Inc.

Kimball, R. (1996) The Data Warehouse Toolkit. John Wiley & Sons, Inc.

Questions?