DuckDB Iceberg MERGE, PostgreSQL GUCs, SQLite Optimization Checklist

DuckDB Iceberg MERGE, PostgreSQL GUCs, SQLite Optimization Checklist Today's Highlights This week's highlights include powerful new Iceberg data manipulation features in DuckDB v1.5.3 and a deep dive into an obscure PostgreSQL GUC. Plus, the SQLite community discusses a practical optimization checklist for embedded databases. New DuckDB-Iceberg Features in v1.5.3 (DuckDB Blog) Source: https://duckdb.org/2026/05/29/new-iceberg-features.html The latest DuckDB v1.5.3 release significantly enhances its integration with Apache Iceberg, introducing a suite of powerful new features for data engineers and analysts. Key among these are the support for MERGE INTO and ALTER TABLE statements, allowing for more robust data manipulation directly within DuckDB for Iceberg tables. This update enables complex operations like upserting data based on conditions, schema evolution (e.g., adding/dropping columns), and modifying table properties, all achievable through a familiar SQL environment. This capability is crucial for maintaining data integrity and adapting schemas without complex external tooling. Furthermore, DuckDB-Iceberg now supports partition transforms, making it easier to manage and query partitioned Iceberg datasets efficiently by defining how data is distributed across files. The release also brings support for Iceberg V3, ensuring compatibility with the latest features of the Iceberg format, including new manifest list and manifest file layouts which offer performance improvements. These additions position DuckDB as an even stronger tool for building performant data pipelines and performing complex analytics directly on large-scale Iceberg data lakes, fully leveraging DuckDB's in-process analytical capabilities and the flexibility of the Iceberg table format. Comment: This update is a game-changer for working with Iceberg tables directly in DuckDB. MERGE INTO support means simplified ETL for incremental loads, and V3 compatibility ensures we're ready for future Iceberg