Data Warehouse / ETL Testing

RTTS provides an automated approach to testing your data warehouses

Data Warehouse / ETL Testing


Testing a data warehouse is challenging and complex. Some of the main challenges to test for when building a data warehouse are:

  • Data Completeness
  • Data Transformation
  • Data Quality
  • Regression Testing

The only way to perform these tests in a reasonable time frame, which will compare huge volumes of data, is through automating the tests.

The Biggest Issues With Data Warehouse Testing

The #1 method to compare data from sources and target data warehouse – sampling, also known as stare and compare — is an attempt to verify data dumped into Excel spreadsheets by viewing or eyeballing” the data. Less than 10% is usually verified and reporting is manual.

Comparison of the data is done by extracting data from source data stores and the target data warehouse using SQL Editors and then dumping results to Excel to stare and compare” (also known as sampling), meaning verifying the data by eyeballing” the results.

This is a huge problem because 1 test query can return as many as 100 million rows with 200 columns, making it impossible to find data errors.

Data testing method stare compare
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This method requires SQL programming and very few testers, analysts, or operations people know SQL.

Expert Big Data Testers + Free Usage Of QuerySurge = Success

Expert BI Testers + Free Usage Of QuerySurge = Success!
  • Our highly skilled Data Test Engineers will provide you with planning and implementation solutions for your Data Warehouse project.
  • And RTTS’ QuerySurge, the smart Data Testing solution, will help us to automate the validation & testing of Data Warehouses quickly.

And QuerySurge is free with our Data Testing Solution! We offer both on-site testing and Testing-in-the-Cloud (from our New York offices).


Please fill out the form below if you require more information or wish to speak with us about our Big Data Testing Solution.