Data testing
Data testing is the systematic verification of data against expected correctness, completeness, consistency, validity, and other quality requirements.
Delivering Machine Learning Projects: From design to deployment
Data testing is the automated checking of data values, distributions, relationships, and construction rules against expected conditions.
- How it is used
- Checks data flowing through development and production pipelines so model work relies on data with expected properties.
- How deep it goes
- Provides test categories, concrete checks, and cost guidance, but does not specify a testing framework or full implementation.
- Examples
- Uses duplicate records, arrival volumes, missing columns, sensor-related nulls, distribution bounds, and incorrectly constructed features.
- What you can do after
- Build it from scratch by turning survey findings and pipeline expectations into checks that continue into production.
Read how Delivering Machine Learning Projects: From design to deployment explains data testing →
Snowflake Data Engineering
Data testing is the practice of systematically checking data against expected correctness, completeness, consistency, validity, and other quality conditions.
- How it is used
- Adds quality-validation steps and response actions to data pipelines so analytics consumers can use data confidently.
- How deep it goes
- Develops task-based checks, violation logging, scheduled metric functions, and alerts, while recommending additional tests for thorough coverage.
- Examples
- Uses PARTNER and PRODUCT loads with a null rating and invalid category, recorded in DQ_LOG by dependent tasks.
- What you can do after
- Operate/configure it through pipeline tasks, logging, scheduled data metric functions, and alerts for quality violations.
Related concepts
- data qualitymeasures · Data quality is the degree to which data is accurate, complete, consistent, relevant, and suitable for its intended use.
- quality measuremeasures · A quality measure is a criterion or quantitative indicator used to assess one or more quality attributes of data, products, processes, or outcomes.
- pipelinepart of · A pipeline is an ordered or coordinated sequence of connected processing stages or tasks that passes data, work, or results toward an outcome.
- data metric functionimplemented by · A data metric function is a Snowflake function that evaluates a data quality metric for an assigned table or view on a defined schedule.
- data integritymeasures · Data integrity is the property that data remains accurate, complete, consistent, and valid, with changes made only through authorized actions.
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