Learning to L ve Data Warehouse Testing

Transcription

1 Learning to L ve Data Warehouse Testing Jackie McDougall jmcdougall@uk.sopragroup.com T A L E N T E D T O G E T H E R Unissons nos Talents 1

2 Agenda Investigating Data Warehouses Project Background Testing Approach Client plan Ideal My Initial Thoughts My View Lessons Learned The Way Forward 2

3 Investigating Data Warehouses THE TRUTH IS OUT THERE 3

4 Investigating Data Warehouses What is a data warehouse? A warehouse is a subject-orientated, integrated, time-variant and non-volatile collection of data in support of management s decision making process Source: What is a Data Warehouse? W.H. Inmon, 1995 A data warehouse is a copy of transaction data specifically structured for query and analysis. Source: The Data Warehouse Toolkit R. Kimball, 1996 A Data Warehouse is NOT a traditional relational database What s the difference? 4

5 Project Background UK Public sector client Government directive to achieve certain heat targets by next year Solution was going to be ETL of data from existing sources to single Data Warehouse Third party providing warehouse solution Reports to ascertain if/when threshold levels reached/breached 5

6 Testing Approach the Client s Plan Warehouse Implemented 14 th 17 th Dec Redevelopment 28 th Jan 3 rd Feb Redevelopment 10 th 16 th Mar Live 26 th Apr Ref Data & Data Load Test 18 th Dec 6 th Jan Pathway Matching 14 th 20 th User Report Testing 31 st Mar 21 st Apr Validation Test 7 th 13 th Dec 2009 January 2010 February 2010 March 2010 April 2010 Test Preparation 9 th Jan 27 th Feb Real-time DL & Report Testing Archive DL & Report Testing 17 th 30 th Mar 3 rd Feb 9 th Mar Key: Dev Team IT Project Team Info Dept Users 6

7 Testing Approach Ideal E T L U Source Data Staging Data ETL Target (DW) Reports Count records In source files Count records in each part of staging Count records In target (DW) Check all fields (directly extracted and derived/calculated) 3rd Party Supplier System Test Count target displayed in reports Check all fields displayed in reports 7

8 Testing Approach My Initial Thoughts Test resources Test Manager brought in Engaged with other users (Data Quality staff, Info Dept testers, (beta) testers) Formal test strategy What Environment What Data Inclusions/Exclusions Resources Acceptance Criteria Stripped back test scripts Release Process Defect Management Risks and Assumptions SIT ETL Requirements Testing Risk Based Testing Scheduled regression testing SIT reports Exploratory Testing UAT ETL Reconciliation Acceptance criteria UAT - reports early previews 8

9 Testing Approach My View r E T L U Source Data Staging Data ETL Target (DW) Reports Sample check data load of transaction data and reference data Sample check data validation/ error process Sample check key fields for calculated/ derived data TOP 10 COMMON PATHWAYS Perfect (RISK world BASED/ testing SCENARIO APPROACH) Project Team Pre-UAT/ Sanity check User Acceptance Testing Reconciliation Reports 9

10 Testing Approach My View (SIT) 10

11 Lessons Learned Define your quality entry criteria that you expect from your supplier Insist your development team/supplier provides adequate design/development documentation Get the requirements right (or at least fixed!) and test them Consider data quality and when it gets addressed Get a test strategy (a real one) Get the right (skilled) resources on board (early) Think carefully about the reconciliation exercise Consider how (the project team) will support the solution going forward 11

12 The Way Forward? Phase 1 Testing? still ongoing Independent Review of solution to aid Phase 2 planning Established test & supporting processes will be maintained Re-use of test scripts and data possible Create a DW testing companion crib sheet for fellow users of things to think about at different stages System Test/SIT examine how I can formalise this with colleagues and use techniques like requirements testing, RBT, exploratory testing to help them UAT promote the Top 10 common pathways approach (combination of RBT/scenario testing) Potential for use of test tools in the future Learn more about DW and BI 12

13 Thank You Advice for me or questions? Jackie McDougall Senior Test Consultant Testing Services Group Carnbroe House, Finch Way Strathclyde Business Park Bellshill, North Lanarkshire ML4 3PR Tel : +44(0) Mob:+44(0) Mail : jmcdougall@uk.sopragroup.com 13