Reviewed by Aditya Kumar · Last reviewed 2026-03-24
(1) Row count—alert on variance. (2) Checksum—MD5/CRC32 of key cols or concat. (3) Sampling—random samples for complex schema. (4) Anti-join—missing/extra rows. (5) Aggregates—SUM, AVG. (6) dbt ref() and freshness. SCALABILITY: Partition-level checks for large tables....
(1) Row count—alert on variance. (2) Checksum—MD5/CRC32 of key cols or concat. (3) Sampling—random samples for complex schema. (4) Anti-join—missing/extra rows. (5) Aggregates—SUM, AVG. (6) dbt ref() and freshness. SCALABILITY: Partition-level checks for large tables. COST: Full checks expensive; checksum + sample balances confidence and cost.
Red Flag: Only row count. Pro-Move: 'We run post-load: count + checksum per partition; full anti-join weekly; automated in pipeline with 0.01% tolerance.'
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