Resolving concurrent write conflicts for Apache Iceberg tables in Amazon Redshift

Amazon Redshift now automatically resolves concurrent write conflicts for Apache Iceberg tables by rebasing non-overlapping changes instead of aborting them.

• Escalates conflict checks from operation-level to partition-level to file-level granularity
• Resolves any write alongside concurrent appends, and row-level writes to different partitions or files
• Eliminates need to serialize writers, partition tables, or implement application-side retry loops
• Improves write throughput by up to 12x at 16 concurrent writers with no rejected commits
• Reduced concurrent-write conflict errors to nearly zero after fleet deployment in September 2026
• Available on patch 203 or later with no configuration required

Automatic conflict resolution enables production data lakes to handle concurrent writes safely while maintaining snapshot isolation semantics and data correctness.