Stoolap Files

What's New in v0.2.1

AS OF Temporal Queries in JOINs

• Support for AS OF TIMESTAMP and AS OF TRANSACTION in JOIN clauses

• Compare current vs historical data in a single query:

  :::sql SELECT c.price AS current_price, h.price AS old_price FROM products c JOIN products AS OF TIMESTAMP '2024-01-01' h ON c.id = h.id WHERE c.price != h.price;

Performance Optimizations

Memory & Allocation Improvements: - Arc-based Row storage with three-tier optimization (Inline/Owned/Shared) - HashMap pooling in VersionStore (~99% allocation reduction for bulk inserts) - Arena slot reuse to prevent unbounded growth on updates - SmallVec for aggregation states and function args

AST Optimizations: - CompactString for inline storage (≤24 bytes avoids heap allocation) - Box large enum variants reducing Expression size from ~400 to ~64 bytes - Pre-computed lowercase fields instead of runtime conversion

Query Execution: - Optimized hash joins with cached NULL rows - TopNResult with pre-extracted sort keys for O(1) comparisons - raw_entry_mut API in GROUP BY (avoids key cloning)

Bug Fixes

• Fix INNER JOIN returning 0 rows with parameters (#4) Thanks to @nhansiromeo
• Fix SubquerySource filter application
• Proper resource cleanup with Drop impl for Database

Other Changes

• Add DuckDB benchmark with optional feature flags
• Version info now uses Cargo.toml as single source of truth
• Improved README with feature comparison tables

Full Changelog: https://github.com/stoolap/stoolap/compare/v0.2.0...v0.2.1