May 2025 monthly summary for apache/spark: Focused on caching correctness for DataFrames created from INSERT statements in Spark SQL, implementing a fix to prevent unintended re-execution during caching; this work reduces data mutation risk and improves cache reliability across workloads.

January 2025 monthly summary for repository xupefei/delta: Delta Lake Kernel improvements focused on delivering row-tracking and metadata management for AddFile actions. Implemented foundational row-tracking for added files, including base row IDs, default row commit versions, and a maintained rowIdHighWaterMark. Ensured domainMetadata presence in table features and added robust error handling for missing statistics and updated feature checks. These changes enhance data lineage, auditability, and reliability of Delta Log metadata, enabling more trustworthy data pipelines and governance.

December 2024 monthly summary for xupefei/delta: Delivered foundational metadata-domain architecture to support JSON-configured domains, enabling scalable metadata management and future row ID assignment. Implemented JsonMetadataDomain as an abstract base class and RowTrackingMetadataDomain with a high-water mark for row IDs. Added comprehensive unit and integration tests to verify serialization and deserialization. Change committed under kernel scope as [Kernel] Add JsonMetadataDomain and RowTrackingMetadataDomain (#3893). Focused on business value and reliability, establishing the groundwork for metadata-driven features and better data lineage.

November 2024: Delivered Domain Metadata Support in Delta Kernel to enable domain-specific configurations and robust transaction handling, including metadata validation for duplicates and protocol support; ensured domain metadata is preserved during checkpointing and log replay. This work lays groundwork for domain-metadata-based conflict resolution between transactions and improves configurability and reliability across the Delta subsystem. Commit 700bdafbb5a43de8b070f9ad3fc7f2fcefeb8e49.