Kaisen Kang

I'm Kaisen Kang

I'm a Database Engineer currently residing in Singapore. I focus on OLAP database query engine.

Check out my public shares

My Public Shares

These are some of my public sharing

How vectorization improves database performance How vectorization improves database performance How to build a high performance vectorized execution engine How to build an extremely fast database How to build an extremely fast database Share the methodology of building an extremely fast database from multiple perspectives How to build an extremely fast vectorization engine How to build an extremely fast vectorization engine Everything about Database Vectorization

Check out my projects

My OLAP database contributions

Over the past ten years, I have been actively involved in OLAP database-related work, making significant contributions to the open-source communities of Apache Kylin, Apache Doris, and StarRocks.

  • OLAP Database Performance Tuning Guide

    • Fundamentals of Performance Optimization
    • Database Principles
    • Performance Optimization Methodology
    • Performance Optimization Tools
    • Performance Optimization Case Studies
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  • StarRocks

    • My team and I built an extremely fast StarRocks query engine, including:
    • StarRocks Vectorized Execution Engine
    • StarRocks Cost-based Query Optimizer
    • StarRocks Pipeline Execution Engine
    • Global Low Cardinality Dictionary Optimization
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  • Apache Doris

    • Built Meituan Doris OLAP analysis platform from scratch.
    • Implemented the Colocate Join, resulting in a performance improvement of 3 to 6 times.
    • Completed multi-instance parallel optimization, enhancing query performance by 3 to 5 times.
    • Developed precise count distinct and user behavior analysis features based on Bitmap technology, significantly improving the performance of precise count distinct queries in Doris by orders of magnitude.
    • Contributed over 100 commits to the Apache Doris.
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    • View All My Projects

    Some of my writing

    My Writings

    Here are some of my recent database posts.

    How to build an extremely fast analytical database - Part1

    Precomputation vs on-the-fly computation:Materialized View,Aggregation Table, Index, Cache, Generated Column

    Posted on Jun 15, 2023

    How to build an extremely fast analytical database - Part2

    Scalability: Multi nodes scalability, multi cores scalability, maximize single-core CPU performance

    Posted on Jun 16, 2023

    How to build an extremely fast analytical database - Part3

    Query data stream processing: Query Optimizer, Query Scheduler, Query Executor, Storage Layer, Vectorized Executor

    Posted on Jun 16, 2023

    How to build an extremely fast analytical database - Part4

    Resource Utilization, Manual Tuning vs. Adaptive Tuning vs. AI Tuning, Extreme Elasticity in Serverless, Architecture vs. Details, Approximate vs. Exact, Performance testing

    Posted on Jun 16, 2023
    ✦ Kaisen

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