April 2026 – Apache DataFusion: SQL Planner schema consistency fixes for semi- and anti-joins, with regression test enhancements. Key changes fix a bug where swapping tables with identical structures could cause schema mismatches in semi- and anti-join scenarios and update exclude_using_columns to reflect join type. Added regression tests (e.g., test_using_join_wildcard_schema_semi_anti) to validate behavior and prevent regressions. Impact: improved correctness and reliability of query planning for semi/anti-join queries, reducing user-visible errors and ensuring consistent results across swapped-table scenarios. Technologies: Rust, DataFusion join semantics, regression testing, code in datafusion/expr/src/utils.rs; collaboration through PR."

March 2026: Fixed a critical division-by-zero bug in VortexOpener when opening empty files, added tests, and aligned zero-length handling with total_size=0 logic. Result: more robust, crash-free file opening and reliable stream generation for zero-row inputs; performance and reliability improvements across data ingestion workflows.