Sequelize associations not generating foreign key - mysql

Question

Sequelize is not creating the foreign key automatically, and is throwing a "no column "userId" in "fieldset"" error. I try to provide all the information down below. Im completely stuck on where to go from here as my code is 100% correct. (Read below)
So i have a Product and User model. both before were working fine. I added some code to set up the relationship:
Product.belongsTo(User, { constraints: true, onUpdate: "CASCADE" });
User.hasMany(Product);
I also, when syncing the db, have used {force: true} and removed it after tables were refreshed. Ive tried restarting pc after these steps, restarting workbench, creating a new database and changing connection to connect to fresh one, still it doesnt put a "userId" column in my product schema.
Ive had this code checked by two people so far and they confirm my syntax is fine, and are equally baffled. Im also confident myself that its not incorrect because im following a reputable course and i've now had to copy and paste his code in replacement to mine just incase, which didnt work.
Product model:
const Sequelize = require("sequelize");
const sequelize = require("../util/database");
const Product = sequelize.define("product", {
id: {
type: Sequelize.INTEGER,
autoIncrement: true,
allowNull: false,
primaryKey: true,
},
title: Sequelize.STRING,
price: {
type: Sequelize.DOUBLE,
allowNull: false,
},
image_url: {
type: Sequelize.STRING,
allowNull: false,
},
description: {
type: Sequelize.STRING,
allowNull: false,
},
});
module.exports = Product;
User model:
const Sequelize = require("sequelize");
const sequelize = require("../util/database");
const User = sequelize.define("user", {
id: {
type: Sequelize.INTEGER,
autoIncrement: true,
allowNull: false,
primaryKey: true,
},
name: Sequelize.STRING,
email: Sequelize.STRING,
});
module.exports = User;
Syncing code (I create a test user as the course is at a stage where we are testing we can make one):
// db.sync({ force: true })
db.sync()
.then((result) => {
return User.findByPk(1);
// console.log(result);
})
.then((user) => {
if (!user) {
return User.create({ name: "Max", email: "test#test.com" });
}
return user;
})
.then((user) => {
app.listen(5000);
})
.catch((err) => {
console.log(err);
});
The connection is 100% connected as things happen to the tables in my database, just the "userId" column which sequelize should auto-generate from my associations doesnt come up.
Also have tried putting in a foreignKey: "userId" in my Product.belongsTo() line of code to try to implicitly set it. That didnt even work.
Therefore im stuck and cannot continue with my sql code.
Github repo if need further code:
https://github.com/NinjaInShade/online-shop

Answer 1

I tried your code with some modifications about associations and foreign keys and you have two ways to create a column userId and a foreign key:
Add a userId field definition to Product model with references option like this:
userId: {
allowNull: true,
type: Sequelize.INTEGER,
references: {
model: 'users',
key: 'id'
}
}
Synchronize models individually using their sync method:
User.sync({ force: true })
.then(() => {
Product.sync({ force: true }).then(() => {
app.listen(5000);
})
})
Unfortunately the official documentation does not clarify why sync method in Sequelize acts differently in comparison with sync of separate models.
Usually I use migrations and that's why I don't have this issue.