Bingnan Chen ChampionNan

Who is ChampionNan?

Hello! I'm ChampionNan — a Database PhD Student bridging the gap between theoretical research and practical system engineering.

Designing query evaluation & optimization.
Bridging theoretical bounds with practical code.
Architecting high-performance database kernels.
Engineering systems that scale with data.

Tech Stack & Skills

Skill Proficiency Levels

🛠️ Systems & Core

🗄️ Database Systems

⚙️ Tools & Environment

Featured Research & Systems & Projects

Project & Research	Core Contributions & Statistics	Status
Yannakakis+ (DuckDB) (Core Optimizer)	• Replaced native join optimizer with Greedy GYO-based enumerator. • Implemented Bloom Filters to replace expensive semi-joins. • Hybrid CBO/RBO using DuckDB's advanced statistics.	🚀 Live
Yannakakis+ (Query Rewriter) (Algorithm Design)	• $O(N+M)$ time guarantee on free-connex queries. • $O(min(NM, F))$ on general queries. • Interleaves selective aggregation-joins with semi-joins.	📜 Published
Quorion System (Interactive Web UI)	• SQL-to-SQL Rewriter for next-gen join plans. • Targets DuckDB, Postgres, MySQL via JDBC. • Visual plan selection & cost-based optimization.	🖥️ System
Flexway O-Sort (Secure Hardware)	• $O(N log N)$ optimal oblivious sorting. • Designed for Intel SGX (Enclave-friendly). • Novel Flexway Butterfly Network for optimal page swaps.	🔒 Security
RISC-V Implementation (Computer Architecture)	• Designed a custom RISC-V processor core. • Validated logic for arithmetic and branch operations.	⚙️ Arch
C-Minus Compiler (Compiler Design)	• End-to-End compilation pipeline (Lexer to CodeGen). • Implemented Syntax-Directed Translation for C subset. • Features intermediate code generation and symbol table logic.	🔧 Tool