Data Warehouse Testing

MagenTys specialises in Data Migration and Data Warehouse testing, with extensive experience at major global and UK companies implementing business critical Management Information, Business Intelligence or Data Warehouse systems.

Our testing solution is designed to overcome the 10 top challenges in data warehouse testing:

• Leaving out the users. Business users are the reason the Data Warehouse exists. Lack of user involvement during the testing phase of system development denies critical expertise during system delivery.
• Testing reports – not data. Testing the system’s reports is not enough. Generating accurate reports is only possible if the underlying data is accurate.
• Extract, transform and load (ETL). Testing should be a priority. Reconciliation of Warehouse Data with Source System Data is critical in ensuring business users are confident all information is accurate, according to business requirements and mapping rules.
• Underestimating the testing workload. Through the use of ETL tools, a minimal amount of code may be written for the testing phase. But this can be very misleading in terms of gauging time. The amount of code cannot predict the number of data issues that testing will uncover.
• Failing to set realistic expectations. While data validation tests can be very thorough, they typically cannot address every possible data issue that will occur.
• Fast-tracking the initial load of a data warehouse is a very time consuming process. Make sure there is a certain level of comfort with the quality of data being loaded into the warehouse before investing several days, in some cases weeks, executing ETL processes.
• Underestimating the ETL process. Make sure that the ETL load processing time fits within the existing batch window.
• Choosing the right testers. The impulse to cut costs is strong, especially in the final delivery phase. A common mistake is to delegate testing responsibilities to resources with limited technology and business experience.
• Avoiding proper sign-off. The paper trail is a bit like the police force. Everyone avoids it until it is needed. Get sign-offs on all phases of testing or stop the project.
• Sufficient cut of test data. Use subsets of production test data for all tests, especially system and user acceptance testing.

MagenTys has a standardised Data Warehouse test strategy and automated framework that can be applied across any platform and technonogy. We can demonstrate the following testing experience within BI/DW: 

ETL Tools: Oracle Warehouse Builder (OWB), Oracle Data Integrator (ODI), Informatica, Ab Initio

Presentation Layer/BI Tool: Oracle Business Intelligence Enterprise Edition (OBIEE), Business Objects, MicroStrategy, Cognos, QlikView

Database: Oracle, DB2, SQL Server, Netezza

Automated Test Tools: HP Quick Test Professional, HP Loadrunner, HP WebInspect

Case Studies:

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