2025-04-08 Another “cultural difference”: butter comes in singular 200g blocks that are big and flat, like a bar of soap...…
- Also known as: lidavidm, otherdavidli,
李增明 ,リー・デイビッド - Email: li.davidm96@gmail.com
- GitHub: @lidavidm
- Currently: Columnar Technologies
- Formerly:
- Voltron Data (aka Ursa Computing; 2021-2025)
- Two Sigma (2018–2021)
Projects
A cross-language and columnar database access abstraction for Apache Arrow.
A cross-language standard for in-memory columnar data.
PMC member.
The third iteration of a programming competition run by Two Sigma.
A game intended to teach programming comprehension, developed for a university research project.
A web platformer/puzzle game, developed for a university course.
The second iteration of a programming competition run by Two Sigma.
A game intended to teach object-oriented programming comprehension, developed for a university course.
A vaguely Wolfram|Alpha-like site powered by the SymPy symbolic algebra library. Can perform integrals (with steps), plot functions, and so on.
Talks & Writings
- (talk)
"Taking Arrow Flight Supersonic"
presented at
Apache Arrow東京ミートアップ2025 (slides) - (blog) "Data Wants to Be Free: Fast Data Exchange with Apache Arrow" (with Ian Cook, Matt Topol)
- (blog) "How the Apache Arrow Format Accelerates Query Result Transfer" (primary author Ian Cook, additional author Matt Topol)
- (lightning talk) "ADBC: Connecting PostgreSQL with Analytics" presented at PostgreSQL Conference Japan 2024 (with Sutou Kouhei) (slides)
- (blog) "Arrow Database Connectivity: Apache Arrow for Every Database User" (archive)
- (blog) "Apache Arrow Flight SQL: Arrow for Every Database Developer" (archive)
- (talk) "Arrow in Flight: New Developments in Data Connectivity" presented at Altinity OSA Con 2022 (slides)
- (blog) "Expanding Arrow's Reach with a JDBC Driver for Arrow Flight SQL"
- (blog) "Simplifying database connectivity with Arrow Flight SQL and ADBC" (archive)
- (blog) "Serving Dataframes Over the Wire with Arrow Flight SQL and DuckDB" (archive)
- (blog) "Introducing Arrow Flight SQL: The All-Star Database Connector" (archive)
- (blog) "Data Transfer at the Speed of Flight" (archive)
- (talk) "Arrow Flight SQL: Accelerating Database Access" presented at The Data Thread 2022 (with James Duong) (slide)
- (blog) "Apache Arrow Flight: A Primer" (archive)
- (podcast) "GreyBeards talk high-speed database access using Apache Arrow Flight, with James Duong and David Li" (audio, transcript, archive)
- (blog) "Introducing Apache Arrow Flight SQL: Accelerating Database Access"
- (blog) "Skyhook: Bringing Computation to Storage with Apache Arrow"
- (talk) "Faster, Simpler Tabular Data Access with Apache Arrow" presented at CROSS Research Symposium 2021 (with Wes McKinney) (slides, recording)
- (talk) "SymPy Gamma and SymPy Live: Python and Mathematics Online" presented at SciPy 2013
Posts
2025-03-06 I found another source for evaporated milk: it turns out Gyomu Super does carry it. Either it was out...…
2025-02-02 I’m surprised that domestic Japanese flights do not check your ID! Just scan your boarding pass and go. Unthinkable...…
If you’re using earthly and it fails with a message like failed: unlazy force execution: failed to load LLB: security.insecure...…
The manga A Report On How I Woke Up One Morning As My Pregnant Wife: New Parents1 referenced an interesting...…
The Sapporo Snow Festival has been interesting. As with tourism in Japan in general, everything is overrun (of course, I’m...…
2025-01-26 I bought a manual lens since it was cheap and have been trying to figure it out. Some notes...…
明けましておめでとうございます！ 新年快乐！ As always, I would like to write more in the future. 2023 and 2024 ended up with me...…
2024-12-09 I finally found condensed milk: it was at National Azabu, an explicitly expat-focused supermarket. The wine person there (an...…
2024-11-05 Well, I’m back from an attempt to cycle the Shimanami Kaido. This trip didn’t quite work out… The remnants...…
2024-10-09 I visited family in China for the first time in about 15 years. I don’t recall the last visit...…
2024-09-01 A coworker recently asked me about culture shocks and I didn’t have a great answer, so maybe here’s some...…
One of the sites that expats in Japan will likely use is iHerb, in order to get various products from...…
Random thoughts on various things I’ve been reading. (Mostly manga, so you, dear reader, should probably close this post and...…
2024-08-04 (Sunday) Pho Thin, despite being highly recommended, doesn’t even compare to the most basic of American pho shops. Of...…
Just random thoughts that would be tweets, except I don’t use Twitter. 2024-07-06 (Saturday) Costco Japan: not as good as...…
Recently, I was debugging some problem where it appeared that std::condition_variable::wait_until would hold the lock and never release it while...…
Emacs was occasionally hanging on me when I tried to save the buffer. This would consistently happen on XML files...…
Sometimes I find myself debugging native code inside a Python program (i.e., an extension module) and want to see the...…
A little line I liked from 町田くんの世界 (Machida-kun no Sekai) by ANDOU Yuki: I like the rain…On your days off...…
Title: アリスとテレスのまぼろし工場 (Arisu to teresu no maboroshi koujou) 1 Synopsis: The film centers on third-year middle school student Masamune, who...…
I’ve had a reMarkable 2 for a couple years now. Overall, I wouldn’t recommend it for reading. Hardware quality is...…
Tottori is the capital of Tottori Prefecture, Japan, on the western (northern) coast. It’s a little out of the way...…
A short story included in Rakuen le Paradis issue 38. The editors describe it thus: オトナ女性二人と少女の過去・現在・未来。 Translated: The past, present,...…
JDBC lets you get the types of the parameters of a prepared statement, and the types of the result set,...…
A fairly hilarious discovery today while reading アリスとテレスのまぼろし工場: one way to call something “Western” is to describe it as batakusai...…
mypy’s stubgen generates something like this for enums: import enum from typing import ClassVar class StatusCode(enum.IntEnum): ALREADY_EXISTS: ClassVar[StatusCode] = ......…
clang-tidy might complain it can’t find headers that it should be able to find as a matter of course: c/driver/postgresql/connection.h:20:10:...…