A team hardening silver tables in Unity Catalog debates how far the database itself will enforce data quality: - "If we add a PRIMARY KEY, duplicate keys can never be inserted." - "CHECK constraints only warn the writer; the row is still committed." - "NOT NULL can only be set at CREATE TABLE time." Which statement about table constraints in Databricks is correct?
Reveal answer
Correct answer: NOT NULL and CHECK are enforced on writes; PRIMARY KEY and FOREIGN KEY are informational only
Reference: https://docs.databricks.com/aws/en/tables/constraints
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02 — The Myelin Layer · Canonical Discussion
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Official Answer (C): NOT NULL and CHECK are enforced on writes; PRIMARY KEY and FOREIGN KEY are informational only
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