March 2026 monthly summary for apache/calcite. Focused on correctness, stability, and collaboration workflow across the Calcite codebase. Delivered key SQL semantics fixes, robust set operation and join rewrites, decorrelation enhancements with improved UNNEST support, and streamlined contributor processes to support long-term maintainability and governance.

February 2026: Delivered critical feature and bug-fix work across vllm-omni and Calcite, focusing on reliability, portability, and correctness in SQL processing and messaging. Key outcomes include a lightweight MessageQueue-based Scheduler, cross-platform compatibility improvements, and multiple bug fixes with tests to prevent regressions. Business value was enhanced through reduced runtime risks, simpler maintenance, and more predictable query behavior across platforms.

January 2026 monthly summary: Focused on stabilizing the optimizer, expanding SQL compatibility, and advancing analytics capabilities across Calcite-based projects. Delivered new function support, strengthened query planning for complex correlations, and expanded test resources to improve reliability. Business value was enhanced by enabling broader Spark analytics with Calcite, reducing edge-case production issues, and laying a solid foundation for future performance improvements across both Calcite and Doris integrations.

December 2025: Expanded Calcite's SQL coverage and optimizer robustness, delivering expressive syntax, stronger correctness guarantees, and clearer planning paths. The work enhances business value by enabling more expressive queries, reducing plan regressions, and improving test reliability for future migrations and performance tuning.

November 2025: Strengthened Calcite SQL processing robustness, expanded SQLite join compatibility, and expanded regression coverage to prevent regressions across engines. Key work included a broad set of correctness fixes in SQL planning and translation (EXISTS/NOT EXISTS, subqueries in JOIN ON, decorrelation tests, rollups, and infinite predicate loops), fixes for translation to MySQL for Semi Join, and added SQLite RIGHT/FULL JOIN support via left-join rewrites for older SQLite versions. The work delivers business value by increasing reliability, breadth of compatibility, and deployment options across SQLite and MySQL, while maintaining consistent results.

October 2025: Delivered foundational Functional Dependency (FD) metadata support in Calcite's RelMetadataQuery, enabling advanced query analysis and optimization with caching and ArrowSet FD minimization. Fixed critical edge cases: preserved fetch/offset in SortRemoveDuplicateKeysRule, and corrected CAST_NON_NULL handling in SqlToRelConverter with added tests. Strengthened optimizer capabilities, stability, and test coverage, delivering business value for analytics workloads.

September 2025 delivered a set of stability, compatibility, and dependency improvements across three repositories (apache/calcite, apache/doris, spiceai/datafusion). Key work targeted core SQL correctness, cross-dialect behavior, and build/dependency hygiene, enabling more reliable analytics workloads and easier maintenance. Key features and bugs addressed: - Calcite: Robust BIGINT FETCH/OFFSET handling across SortJoinTransposeRule, SortMergeRule, EnumerableMergeUnionRule and related limit logic to ensure correctness for large OFFSET/FETCH values. - Calcite: MySQL-style non-standard GROUP BY support (wrap non-aggregated columns with ANY_VALUE when nonStrictGroupBy is enabled). - Calcite: PostgreSQL ORDER BY constants compatibility by removing unsupported string-literal keys in ORDER BY. - Calcite: Avatica dependency upgraded from 1.26.0 to 1.27.0 to maintain compatibility with Calcite. - SpiceAI DataFusion: Remote object store URL trailing slash handling to fix breakages in file listing/retrieval and add tests. Overall impact and accomplishments: - Significantly reduced edge-case query failures and incorrect results in large-offset scenarios, improving reliability for large-scale analytics. - Expanded cross-dialect compatibility (MySQL, PostgreSQL) reducing dialect-specific bugs and easing migrations. - Improved build stability and dependency hygiene (ARM builds and library upgrades) enhancing developer experience and CI reliability. - Improved data access auditing and observability through richer metadata in Doris active_queries and better UX with remote stores. Technologies/skills demonstrated: - Java-based rule debugging and regression testing, SQL dialect adaptation, and test coverage. - Dependency management and submodule/CI hygiene (Avatica upgrade, FAISS considerations). - Cross-architecture build considerations (ARM) and CMake-related decisions.

August 2025 monthly summary for Doris and Calcite: Delivered planner optimizations and correctness enhancements across two repositories, driving better performance for grouping-heavy queries and more reliable aggregation results. Key improvements include new and improved planner rules for sort and grouping, targeted bug fixes in GROUP BY semantics, and maintainability work to reduce technical debt.

July 2025 monthly summary focusing on key developer contributions across Calcite, Doris, and related projects. Highlights include delivery of a new FULL JOIN optimization rule, support for functional dependency metadata in RelMetadataQuery, enhanced EXTRACT function usability with day-of-year and day-of-week aliases, expanded unit test coverage for Nereids Show commands, and documentation clarifications improving configuration option descriptions.

June 2025: Delivered key architectural and reliability improvements across Doris and Calcite. Doris FE: migrated 11 legacy Show/Describe/Alter statements to Nereids-based commands, centralizing parsing/execution and removing deprecated statements; Calcite: enhanced Volcano planner sort rule handling for LIMIT/OFFSET/ORDER BY, fixed JDBC SELECT * generation with duplicate field names, and added tests for false-join condition pruning. Impact: reduced maintenance burden, improved query correctness and planning performance, with strengthened cross-repo collaboration and testing coverage. Technologies: Nereids migration, FE architecture, Volcano planner, JDBC dialect handling, test-driven development.

May 2025 performance summary: Across apache/calcite, apache/kvrocks, and apache/doris, delivered targeted features, correctness fixes, and observability improvements that enhance query performance, reliability, and developer experience. Calcite gains include a new MIN/MAX optimization rule, extended n-way IntersectToSemiJoin, and robustness fixes in join/predicate handling and left-join semantics, plus planner/configuration improvements. Kvrocks improvements standardized logging and naming, boosting traceability and maintainability. Doris delivered cross-platform build reliability and enhanced visibility with Show Query Stats and catalog management via Show Catalog Recycle Bin. These changes collectively improve end-to-end query planning, execution efficiency, and operational tooling, enabling faster delivery and easier troubleshooting.

April 2025 performance/optimizer deliverables for apache/calcite focused on advancing set-ops performance, join processing, testing infra, and data-model capabilities. The work improves query plan quality, reduces execution cost, and broadens supported workloads, translating to faster user queries and more robust planning across common analytical patterns.

March 2025 monthly summary for Apache Doris and Calcite integration. This period delivered a broad expansion of the SQL discovery surface via Nereids-driven SHOW commands, strengthened planning performance through targeted optimization rules, and reinforced quality with comprehensive tests. In Doris/Nereids, we introduced and refactored a suite of SHOW commands (SHOW TABLES, SHOW DATA, SHOW COLUMN HISTOGRAM, SHOW TABLE STATUS, SHOW VIEWS, SHOW TABLET ID, SHOW TABLETS FROM, SHOW DATABASES) with grammar, planning, and execution support, and added SHOW INDEX STATS. Also implemented Show Databases, Show Tablet details, and related enhancements with plan construction and execution improvements. Key commits touched include support and refactors across SHOW commands (e.g., 97ad3e4e, 752fc5e), data/column/statistics features (5b12f0e5, 81886fa4), and test/cleanup work (03771221, 8df0b809). In Calcite, added Doris dialect support and core optimization rules (FilterSortTransposeRule, IntersectToExistsRule) plus VolcanoPlanner top-down refactor to improve planning efficiency and execution. Tests and UIs: added privilege tests and system command tests to ensure correct permissions and prevent regressions. Overall impact: broader data discovery capabilities, faster and more efficient query planning, and higher reliability through increased test coverage.

February 2025 focused on strengthening Nereids SQL parsing and runtime, expanding cluster administration capabilities, and stabilizing Calcite rule handling. These efforts improve optimizer accuracy, operational control, and reliability across Doris and Calcite, enabling faster, more predictable query performance and simpler system management.