Takayuki Tsunakawa
Reading time: 7 minutes
PostgreSQL is the World’s most advanced Open Source Relational Database. The interview series “PostgreSQL Person of the Week” presents the people who make the project what it is today. Read all interviews here.
Please tell us about yourself, and where you are from.
I’m a Japanese man who was born and lives in Japan, near Tokyo. I am visually impaired by nature, and I have only enough eyesight to feel the light now. But I had somewhat better vision when I was a child, and enjoyed playing video games with friends or alone. I can’t see the screen, so I use screen reader software that reads characters by synthesized voice.
I’ve been working for Fujitsu after I graduated from a college, and have been engaged in the planning, development, and support of database products.
I’ve been developing in the community in recent several years. I think I’ve done just bug fixes and small improvements, but thankfully, I’m listed in the contributor list. I’m not exactly sure why I was recognized as a contributor, but I feel very pleased and it’s encouraging. I’m a technical manager and have been leading the open source team at Fujitsu in Japan.
I hope that PostgreSQL will become the most popular database in the world and I’ll be part of the great history.

Takayuki Tsunakawa
Last book you read? Or a book you want to recommend to readers?
“Sword Art Online”, a novel of an MMORPG in virtual reality.
How do you spend your free time? What does your ideal weekend look like?
Reading books for learning things or for fun, playing with my kid, drinking wine, watching video for game play on YouTube, watching anime on TV… Oh, I should do exercise!
I also like seeing the popularity score of PostgreSQL increase in DB-Engines.com ranking.
I’m dreaming of becoming able to play role playing games again like when I was a kid. I’m also interested in learning to play musical instruments. I like the sweet notes of a harp.
What is the best advice you ever got?
“A leader is one who knows the way, goes the way, and shows the way.” by John C. Maxwell.
This is not what I got directly, but I like this statement because it describes a leader in very simple terms and I want to be such a forward-looking person.
When did you start using PostgreSQL, and why?
Around 2003, SRA OSS, Inc., a company that Tatsuo Ishii leads as a president, and our database-centric division collaborated to produce a database product called PowerGres Plus based on PostgreSQL 7.3. At that time, PostgreSQL did not scale on SMP machines, did not have media recovery features, and did not run natively on Windows. On the other hand, our company had a high-performance and reliable proprietary database product called Symfoware that ran on mainframe, Unix, Linux and Windows. We defined the storage engine API, cut out and adjust our storage engine from Symfoware to plug it under PostgreSQL’s SQL processor. SRA OSS, Inc. ported PostgreSQL to run natively on Windows.
We achieved CPU scalability and 2x+ performance compared to open source PostgreSQL on SMP machines, PITR to recover the latest data up to the point of failure, database corruption detection using checksum, and native support for Windows. That’s my fortunate encounter with PostgreSQL.
Do you remember which version of PostgreSQL you started with?
7.3, that’s what PowerGres Plus was based on.
Have you studied at a university? If yes, was it related to computers? Did your study help you with your current job?
I studied computer science at a 3-year college. Yes, it directly led to my current job. And now, I’ve applied for an online university to learn human information science starting next April. I hope I will pass the exam.
What other databases are you using? Which one is your favorite?
99% of the time I’m PostgreSQL. But Oracle is surely a respectable database that I want to learn from, catch up and beat someday. It’s nice that there exists a goal ahead.
On which PostgreSQL-related projects are you currently working?
I was active in psqlODBC for some time, and was given a committer privilege. I’ve been away from there due to other tasks, but I’d like to go back and contribute again. Unfortunately nothing else yet. However, I have some ideas that I want to realize.
How do you contribute to PostgreSQL?
I’ve been contributing patches for new features, bug fixes and improvements. I’ve also been leading the open source team at my company and help team members contribute to various projects.
Any contributions to PostgreSQL which do not involve writing code?
I’m the creator of the PostgreSQL ecosystem wiki. Thankfully, many people have helped enrich its content.
I’m also a member of PostgreSQL Enterprise Consortium where various companies collaborate to promote PostgreSQL for enterprise use in Japan.
What is your favorite PostgreSQL extension?
Citus. Because it realizes read-write scale-out, which I believe is one of several key features that would make PostgreSQL further popular.
What is the most annoying PostgreSQL thing you can think of? And any chance to fix it?
Shortage of information when troubleshooting, particularly when it comes to performance statistics. I’m inclined to enhance performance statistics to the level comparable with Oracle and MySQL.
What is the feature you like most in the latest PostgreSQL version?
- PostgreSQL 13: B-tree key deduplication
- PostgreSQL 12: Drastic performance enhancement to make thousands of partitions per table feasible
Adding to that, what feature/mechanism would you like to see in PostgreSQL? And why?
There are many. If I dare to give some, the core features are for the 3V of big data – read-write scale-out (Volume), multi-model (Variety), streaming and in-memory processing (Velocity). Plus, an autonomous database that frees dedicated DBAs. I want more performance statistics like Oracle and MySQL to help troubleshooting, which can be the first step toward the autonomous database.
Could you describe your PostgreSQL development toolbox?
Emacs, Git, GCC, Visual Studio – nothing special.
Which skills are a must have for a PostgreSQL developer/user?
The skills for a user are the same as for many other DBMSs, so let me tell you about a PostgreSQL developer. Basic Unix command line operations, basic Git knowledge, GNU Makefile, and C programming are a must. To do more interesting things, you should learn about DBMS in books. I recommend the nearly 30-year-old book “Transaction Processing: Concepts and Techniques”, although it’s more than 1,000 pages!
Do you use any git best practices, which makes working with PostgreSQL easier?
Sorry, nothing. I want to know how active committers do use git on a regular basis. That’s good information to be added to the PostgreSQL Developer information wiki.
Which PostgreSQL conferences do you visit? Do you submit talks?
I’ve had talks at PGCon, PGConf.ASIA, and PostgreSQL Conference Japan. I hope I’ll be able to attend more conferences and talk there, taking advantage of the virtual conference.
Do you think PostgreSQL has a high entry barrier?
No. On the other hand, I think the PostgreSQL wiki needs some refreshing – add the latest information and erase old content not to overwhelm users.
What is your advice for people who want to start PostgreSQL developing - as in, contributing to the project. Where and how should they start?
Everything is in the “Development information” page in the PostgreSQL wiki. Particularly I recommend skimming through the Developer FAQ linked from there. I also recommend starting with bug fixes and small improvements that are likely to be accepted early. Patch acceptance will lead to your self-efficacy and give you the energy for greater work in the future.
Do you think PostgreSQL will be here for many years in the future?
I think so. But what makes me worry is the influence of major cloud providers and acquisitions. I’m afraid PostgreSQL might go away from us, and will be “there” not “here.”
Would you recommend PostgreSQL for business, or for side projects?
Yes, for both. I believe nobody doubts it, because most cloud providers offer DBaaS for PostgreSQL and many open source projects use PostgreSQL.
Are you reading the -hackers mailinglist? Any other list?
Yes, I mostly pay attention to -hackers. I usually see subjects and read what I’m interested in. I used to read some other lists such as -odbc, -interfaces, and -performance, but I haven’t read them recently due to lack of time. I’m hoping to read them again, and help users on multiple channels to know what should be developed for PostgreSQL.
Which other Open Source projects are you involved or interested in?
I’m not involved but interested in Citus, TimescaleDB, upcoming Babelfish from AWS, and game engines.
Anything else you like to add?
I’m pleased to have an opportunity for this interview. Thank you, Andreas.