November 2024
Intermediate to advanced
208 pages
4h 56m
French
Content preview from L'alchimie essentielle de SQLA, 2e édition
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Chapitre 12. Construire des migrations
Cet ouvrage a été traduit à l'aide de l'IA. Tes réactions et tes commentaires sont les bienvenus : translation-feedback@oreilly.com
Au chapitre 11, nous avons initialisé et configuré l'environnement de migration Alembic pour nous préparer à ajouter des classes de données à notre application et à créer des migrations pour les ajouter à notre base de données. Nous allons explorer comment utiliser l'autogénérateur pour ajouter des tables, et comment créer manuellement des migrations pour accomplir des choses que l'autogénérateur ne peut pas faire. C'est toujours une bonne idée de commencer par une migration vide, alors commençons par là car cela nous donne un point de départ propre pour nos migrations.
Générer une migration vide de base
Pour créer la migration vide de base, assure-toi d'être dans le dossier CH12/ du code d'exemple de ce livre. Nous allons créer une migration vide à l'aide de cette commande :
# alembic revision -m "Empty Init"Generatingch12/alembic/versions/8a8a9d067_empty_init.py...done
Exécute la commande
alembic revisionet ajoute le message (-m)"Empty Init"à la migration.
Cela créera un fichier de migration dans le sous-dossier alembic/versions/. Les noms de fichiers commenceront toujours par un hachage qui représente ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.