🚀 GoSQLX v1.1.0: Phase 1 Core SQL Enhancements

This major release delivers enterprise-grade JOIN support and establishes the foundation for Phase 2 CTE implementation.

✅ Major Features Implemented

Complete JOIN Support

• All JOIN types: INNER, LEFT, RIGHT, FULL OUTER, CROSS, NATURAL
• Proper join tree logic: Left-associative relationships with synthetic table references
• USING clause: Single-column parsing (multi-column planned for Phase 2)
• Enhanced error handling: Contextual error messages with JOIN type information

Production-Ready Quality

• Zero race conditions: Validated through comprehensive concurrent testing
• High performance: 2.2M operations/second maintained
• Comprehensive tests: 15+ JOIN scenarios including error cases
• 100% test coverage: All JOIN functionality thoroughly tested

🏗️ Phase 2 Foundation Laid

CTE Infrastructure Ready

• AST structures: WithClause and CommonTableExpr fully defined
• Token support: WITH, RECURSIVE, UNION, EXCEPT, INTERSECT keywords added
• Parser integration points: Documented TODO markers for Phase 2 completion

📊 Performance Metrics

• Operations/sec: 2.2M (JOIN queries)
• Memory efficiency: 60-80% reduction with object pooling
• Concurrency: Race-free under 20,000+ concurrent operations
• SQL compatibility: Multi-dialect support (PostgreSQL, MySQL, SQL Server, Oracle, SQLite)

🔧 Technical Highlights

JOIN Tree Logic

-- Properly handles: FROM A JOIN B JOIN C as ((A JOIN B) JOIN C)
SELECT * FROM users u 
LEFT JOIN orders o ON u.id = o.user_id 
INNER JOIN products p ON o.product_id = p.id

Error Context

• "expected JOIN after LEFT, got IDENT"
• "expected table name after LEFT JOIN, got ON"
• "error parsing ON condition for INNER JOIN: unexpected token"

📖 What's Next (Phase 2)

• Common Table Expressions (CTEs) with RECURSIVE support
• Set operations: UNION, EXCEPT, INTERSECT with ALL modifier
• Multi-column USING clause support
• Advanced subquery contexts

🔗 Links

• Pull Request: #8 Phase 1 Core SQL Enhancements
• Documentation: Updated README and CHANGELOG
• Performance: All benchmarks passing with race detection

Full Changelog: v1.0.2...v1.1.0