Cédric Duprez

Reading time: 7 minutes

Tags:   postgresql (141)   france (17)   pgdayfr (2)   national forest inventory (1)   aikido (1)   postgis (8)   ogr_fdw (2)  
Category:   Interviews   
Interview conducted by: Andreas Scherbaum

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 am Cédric Duprez and I live near Montargis, in the center of France. I work as a database expert in the National Institute of Geographic and Forest Information (IGN), which is the reference public operator for geographic and forest information in France.

I’m managing the national forest inventory data, and I’m DBA for this part of the company. But I’m also helping other DBA or data managers when they need it.

I’m representing IGN in PostgreSQL France.

Cédric Duprez

Cédric Duprez

How do you spend your free time? What are your hobbies?

I’ve been practicing Aikido for a long time and I spend a lot of time on Tatami. I’m also teaching Aikido and I was president of my club for about 10 years.

Any Social Media channels of yours we should be aware of?


Last book you read? Or a book you want to recommend to readers?

At the moment, I’m finishing the Don Winslow’s Cartel trilogy. The last book is called The Border. I enjoy reading thrillers, but also historical novels. I recommend the wonderful Earth’s Children books by Jean M. Auel.

Any favorite movie, or show?

I enjoy watching comedies, so I would say: Groundhog Day or Monty Python and the Holy Grail, two of my favorite movies, which I re-re-re-…watch with pleasure.

What does your ideal weekend look like?

First of all, spending time with my family. Since I like cooking, preparing a good meal for Sunday is a good thing.

And if I still have some time: a nice Aikido course.

What’s still on your bucket list?

Many various things: tinker in the house, play the guitar again (I learned it when I was young, but I’ve left for a very long time), read all Jules Verne books, learn how to restore an old 2 CV car, and more contributing to PostgreSQL.

What is the best advice you ever got?

Jacques Prévert wrote : “We recognize happiness by the noise it makes when it leaves.” I find this sentence very true, so I always try to enjoy my family, my friends and life in general. Even when things go wrong, which is more difficult…

When did you start using PostgreSQL, and why?

I started using PostgreSQL in 2007, when I was hired by the French national forest inventory. At that time, the RDBMS in use was SQL Server 2000, but the cost was important, especially for using the spatial extension. We did tests on PostgreSQL / PostGIS and realized that it did what we were looking for. 2 years later, all the databases had been migrated to PostgreSQL.

Do you remember which version of PostgreSQL you started with?

It was PostgreSQL 8.2 that we qualified, with PostGIS 1.3.

I studied agricultural sciences and agronomy in a national agricultural college, so nothing related to computers at first glance. But I had courses on computers and data sciences. And these studies probably gave me a different point of view on the questions I try to solve.

What other databases are you using? Which one is your favorite?

IGN is now quite full PostgreSQL. So I’m only using PostgreSQL, but we are starting proof of concept on NoSQL databases (MongoDB) and comparing it to NoSQL capabilities of PostgreSQL. So PostgreSQL is my favorite one.

I’m mostly working on the translation of the PostgreSQL documentation.

How do you contribute to PostgreSQL?

By translating PostgreSQL documentation to French, by teaching PostgreSQL at Orléans university (the university in the region where I live) and by representing PostgreSQL France in different shows.

Any contributions to PostgreSQL which do not involve writing code?

The ones I mentioned earlier, and by attending PGGTIE (French Inter-companies Workgroup). We have a new project in which I’m involved to popularize PostgreSQL by making small technical clips on the web. Since I am not a developper, my contributions to PostgreSQL are not code.

What is your favorite PostgreSQL extension?

Because I work in a geographic institute, I must answer with PostGIS, of course. But I also like ogr_fdw (also related to geographical information) and pg_stat_statements, which are unavoidable in order to optimize PostgreSQL clusters.

What is the most annoying PostgreSQL thing you can think of? And any chance to fix it?

Because the data sets I manage are correlated together, I would say that join selectivity is often underestimated, which leads to bad execution plans. This problem is known and a patch is under review, so I hope it will be fixed in one of the next releases.

What is the feature you like most in the latest PostgreSQL version?

Since I’m interested in JSON types in PostgreSQL, I like the new support of array-style subscripting expressions to extract and modify elements in JSONB. It is closer to the Python language and makes it easier to query JSON data.

Adding to that, what feature/mechanism would you like to see in PostgreSQL? And why?

I’m looking forward to logical replication of sequences. But this should be in the next major version, if I remember well.

Could you describe your PostgreSQL development toolbox?

I manage PostgreSQL with psql, of course, but I also really enjoy querying with DBeaver since the beginning of this project. It’s an amazing tool, really close to an ETL, all in SQL. For geographical features, I usually display PostGIS query results in QGIS.

Which PostgreSQL conferences do you visit? Do you submit talks?

I try to attend pgDay Paris, PgDay France and Dalibo PgSessions every year. I also participate in Paris Opensource Experience, holding the PostgreSQL France stand.

I did a presentation in a Dalibo PgSession about PostgreSQL / PostGIS major version upgrade using logical replication in 2020 (from home, because of Covid), and another presentation with other PostgreSQL specialists in french large companies about PostgreSQL as a development platform in 2021.

Do you think PostgreSQL has a high entry barrier?

No, I don’t think so. PostgreSQL (and SQL) is easy to learn. I’m teaching SQL and PostgreSQL administration at the university and in my company, and the feedback I get is that PostgreSQL is not so hard to learn.

Do you think PostgreSQL will be here for many years in the future?

I’m sure that PostgreSQL will stand for a very long time, because of the community organization, dynamism and the always increasing adoption of PostgreSQL, even by large companies in France and all around the world. The stability of PostgreSQL, the quick improvement of its features, the quickness of bugs resolution, and the numerous projects gravitating around PostgreSQL are other good arguments to be confident in the future.

Would you recommend PostgreSQL for business, or for side projects?

Both of them. I use PostgreSQL for business, because it is robust to manage large databases, but it is also easy enough to implement small side projects. As an example, I participated in the organization of national forest and wildlife inventory in Ivory Coast (which provided a small database in size), and of course I implemented PostgreSQL as SGBDR. It was easily adopted.

Are you reading the -hackers mailinglist? Any other list?

No, I don’t read the -hackers mailing list (because it is too technical for me), but I’m subscribed to the -fr-generale list for a long time.

What other places do you hang out?

Postgis-users mailing list, still because of the geographical part of my job.

Which other Open Source projects are you involved or interested in?

I’ve been following DBeaver since the very beginning of the project. I’m also using PgBadger, temBoard and pgwatch2 for PostgreSQL instance monitoring.

Anything else you like to add?

Yes, I really enjoy this nice blog of interviews. It’s really cool to read about people involved in PostgreSQL, with so many different use cases. And thank you for giving me the opportunity to present myself and to have read my post until the end.