Hello, I’m Louise Grandjonc. I am the lead backend developer at
Ulule. I do a lot of python, SQL and work on the performances of the
platform every day.
I’ve been using PostgreSQL since I’ve started working with
databases (which is not that long ago, about 4 years ago) except a few
dark weeks of MySQL when I was still a student.
Since then I’ve been to as many PostgreSQL conferences as I could
and love the community. I’m really interested in the vulgarisation
of relatively complex concepts, which is why I’ll talk about
explain here at pgDay Paris.
Have you enjoyed previous pgDay Paris
conferences, either as attendee or as speaker?
I have been to the past three editions actually, as an attendee. The
first year I helped Dimitri and Vik for the website.
What will your talk be about, exactly? Why this topic?
I am going to talk about EXPLAIN. I want people to understand what an
execution plan is, and what are the different algorithm used by postgres to
filter, to join tables etc. I’ve chosen this topic because I think
that it’s one of the keys of understanding slow queries and how you
can improve your performances. Moreover as a developer I use a lot ORMs and
knowing when to stop to write better code is important. I did this
conference because I felt like I needed it when I started working with
What existing knowledge should the attendee have?
The attendee should have at least once in their lives written a
“SELECT ... FROM ...” and thought “oh, well,
perhaps I should take a coffee break, that query is taking