Database Technology

Chris van Eijk benchmarks five index configurations across 1,000 tenants in PostgreSQL 17 to determine optimal column ordering for multi-tenant workloads. The analysis reveals that placing tenant_id as the leading column is critical for query performance, particularly when Row Level Security (RLS) alters execution plans. The study also evaluates when table partitioning provides sufficient payoff to justify its complexity.

• Leading with tenant_id ensures efficient index scans for per-tenant queries in multi-tenant schemas.
• RLS can significantly change query plans; verify execution paths after enabling security policies.
• Partitioning only pays off at scale; measure overhead before adopting for small tenant counts.
• PostgreSQL 17 optimizations were tested, but column order principles remain consistent across versions.

Chris van Eijk benchmarks five strategies for generating gapless, unique invoice numbers per tenant in PostgreSQL 17, including sequences, max()+1, SERIALIZABLE transactions, and counter rows. The analysis specifically measures performance, gap occurrence, and duplicate resistance under concurrent load. This provides empirical data to help engineers choose the right concurrency control model for high-throughput billing systems.

• Sequences offer speed but create gaps under high concurrency; assess if gaps are acceptable.
• SERIALIZABLE transactions guarantee no duplicates or gaps but significantly reduce throughput.
• Max()+1 is simple but prone to race conditions without strict locking or serialization.
• Counter row approach balances consistency and performance for multi-tenant isolation.
• PostgreSQL 17 handles these contention patterns efficiently, but locking remains the bottleneck.

Core contributor Robert Haas is hosting a hacking workshop in October 2026 focused on his presentation regarding pg_plan_advice. The session targets plan stability and user-level planner control for PostgreSQL. Participants must sign up via a provided form to receive a session invite.

• Workshop focuses on pg_plan_advice for managing plan stability.
• Target audience includes engineers interested in user planner control.
• Attendance requires registration through the official sign-up form.
• Event is scheduled for October 2026 with specific session invites.
• Led by Robert Haas, a key figure in PostgreSQL core development.

AWS has made PostgreSQL 19 Beta 4 available in the RDS Database Preview Environment, allowing users to evaluate the pre-release version. This build refines query performance and autovacuum management capabilities introduced in earlier betas, alongside stability improvements. Key updates include bug fixes for the pg_stat_autovacuum_scores view and corrected freeze-score scaling for better tuning.

• PostgreSQL 19 Beta 4 is now available for evaluation in the RDS Database Preview Environment
• Autovacuum management improvements include rebalanced cost limits for parallel workers
• Fixes address pg_stat_autovacuum_scores reporting for TOAST tables and freeze-score scaling
• Users can now tune autovacuum prioritization more effectively with corrected scaling metrics

PgBouncer 1.26.0 addresses three critical denial-of-service vulnerabilities triggered by unauthenticated clients or malicious servers, specifically involving SCRAM nonce handling, integer overflows, and unbounded iteration counts. The release introduces functional improvements including tracking of search_path and default_transaction_read_only, new pool_idle_timeout configuration, and per-user/query_wait_timeout settings. Additionally, it adds Meson build support and removes the deprecated online restart (-R) functionality.

• Patch immediately to fix DoS risks from unauthenticated SCRAM and integer overflow attacks.
• Migrate from Make to Meson build system for future compatibility.
• Utilize new pool_idle_timeout and granular query_wait_timeout settings.
• Remove deprecated -R flag usage and verify search_path tracking behavior.
• Monitor for malicious server-side SCRAM iteration count attacks.