I'm trying to understand how sequelize works on a simple example : User can have many posts and post can have only one user.
First question, I don't know if I have to use the migrations or the models with sync for creating my database. I mean, I have to put bearly the same code in both. This is the migration for the users table:
module.exports = {
up: (queryInterface, Sequelize) => {
return queryInterface.createTable('Users', {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
username: {
allowNull: false,
type: Sequelize.STRING,
unique: true
},
password: {
allowNull: false,
type: Sequelize.STRING
},
email: {
allowNull: false,
type: Sequelize.STRING,
unique: true
},
createdAt: {
allowNull: false,
type: Sequelize.DATE
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE
}
});
},
down: (queryInterface, Sequelize) => {
return queryInterface.dropTable('Users');
}
};
And this is the Post model :
'use strict';
module.exports = (sequelize, DataTypes) => {
const User = sequelize.define('User', {
username: DataTypes.STRING,
password: DataTypes.STRING,
email: DataTypes.STRING
}, {
classMethods: {
associate: (models) => {
User.hasMany(models.Post);
}
}
});
return User;
};
Do I also have to specify that the username, email can't be null and must be unique here in the model?
And how do I have to add the foreign key ? In one tutorial, they said me that the database add automaticly the foreign key but I don't think it works if I use the migrations, I have to set it manualy no?
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