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Data & Analytics · Intermediate

Schema Drift

Unplanned changes in a source's structure, such as new, removed or renamed columns or changed types, that can break pipelines.

Definition

Pipelines detect drift with schema validation, rescue columns (Auto Loader's _rescued_data), Data Factory's 'allow schema drift' option in mapping data flows, and data contracts.

Exam tip

Auto Loader's rescued data column captures values that don't match the schema instead of failing.

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