SQL-FUNDAMENTALS5 MIN READ
Sort data quality checks
Use SQL checks to test completeness, validity, consistency, and timeliness.
Completeness Validity Consistency Timeliness COUNT(*) FILTER (WHERE email IS NULL) amount < 0 for a table where refunds have a separate type subscription.status = 'active' while account.status = 'closed' MAX(updated_at) older than the last nightly load window missing region on enterprise accounts country_code not in the ISO reference table
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