Reviewed by Aditya Kumar ¡ Last reviewed 2026-03-24
**ACID**: Atomicity (all or nothing), Consistency (valid state), Isolation (concurrent transactions), Durability (persisted). **Why in data**: Traditional lakes lacked ACIDâconcurrent writes corrupted data. Delta Lake, Iceberg provide ACID via transaction logs: concurrent...
Pro-Move: 'We use Delta for our curated layerâMERGE for upserts, time travel for incident recovery; Iceberg for cross-engine.' Red Flag: Saying 'we don't need ACID' for financial or compliance dataâyou do.
ACID: Atomicity (all or nothing), Consistency (valid state), Isolation (concurrent transactions), Durability (persisted). Why in data: Traditional lakes lacked ACIDâconcurrent writes corrupted data. Delta Lake, Iceberg provide ACID via transaction logs: concurrent writes, time travel, schema evolution. Use cases: Exactly-once processing, compliance, financial. Trade-off: ACID adds metadata overhead; traditional append-only is simpler but can't update/merge. Best practice: Use Delta or Iceberg when you need updates, deletes, merges.
Pro-Move: 'We use Delta for our curated layerâMERGE for upserts, time travel for incident recovery; Iceberg for cross-engine.' Red Flag: Saying 'we don't need ACID' for financial or compliance dataâyou do.
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