TypeORM is one of the most popular ORM for Typescript based projects. 26k stars on GitHub, 815k weekly installs. But is it that good? This is a story of the speaker's relationship with TypeORM: from love to hate and life after. You will learn which common problems may happen with ORMs and where to look when you are choosing ORM for the next project. And if you already using TypeORM, you will recognize yourself and find like-minded people.

1. How to use TypeORM and
stay alive

2. Hello, I am Andrii 👋
💻 Senior Software Engineer at
󰳙 First engineer
from first line of code ➡ $20M Series A
Huge TypeScript fun
🏃 Run OCR from time to time
You see, here I am using TypeORM and I
feel great

3. NO WAY
Answering the question from the first slide

4. Supports 10 databases
Works in NodeJS, browsers, cross-platform
DataMapper and Active record support
… and shit ton of other features

10. Data Schema

12. SELECT * FROM properties
LEFT JOIN photo ...
LEFT JOIN photos_sized ...

13. {
?
Quite wide table

14. 20 X 15 X 5
~ 1500

15. ~ 3s per request

17. Dataloader here to help
https://github.com/graphql/dataloader

18. Magic 🪄

21. Choose your fighter
SELECT
JOIN
JOIN
JOIN
SELECT WHERE id IN
SELECT WHERE id IN
SELECT WHERE id IN

23. Transactions

24. Transaction. The bad way
General way
Decorators way

28. Continuation-Local Storage
(or Thread local vars in Node.js)
Context

30. https://github.com/odavid/typeorm-transactional-cls-hooked

34. #StableReleases

35. All goes bad. What to do?

37. Prisma
“Prisma currently doesn't support the "traditional"
database transaction mechanism”

38. Objection.js
https://vincit.github.io/objection.js/
“Objection.js is ORM for Node.js, which is built on an
SQL query builder called knex”
“All databases supported by knex are supported by
objection.js are thoroughly tested”

39. How does it look like?

40. Jobs board
About Nomad Homes
SELECT * FROM question

41. Happy to see you on my standups interviews