Node.js Sequelize virtual column pulling value from other model - mysql

Question

I'm working with Sequelize 5.7, trying to utilize virtual datatype,
to pull related information into a model.
Given simplified company and user models, how do I get company.name
into user.companyname ?
company
let Schema = sequelize.define(
"company",
{
id: {
type: DataTypes.INTEGER.UNSIGNED,
autoIncrement: true,
primaryKey: true
},
name: {
type: DataTypes.STRING(45)
}
}
);
user
let Schema = sequelize.define(
"user",
{
id: {
type: DataTypes.INTEGER.UNSIGNED,
autoIncrement: true,
primaryKey: true
},
login: {
type: DataTypes.STRING(45),
unique: true
},
company: {
type: DataTypes.INTEGER.UNSIGNED,
references: {
model: sequelize.model('company'),
key: 'id'
}
},
/* This companyname contruct is pure fantasy, and the target of my question */
companyname: {
type: new DataTypes.VIRTUAL(DataTypes.STRING,['company']),
references: {
model: 'company',
key: 'name'
}
}
}
);

Answer 1

In your case, I think it is a better idea to use a relationship (an association)
Sequelize Associations
const User = sequelize.define('user', {
id: {
type: DataTypes.INTEGER.UNSIGNED,
autoIncrement: true,
primaryKey: true
},
login: {
type: DataTypes.STRING(45),
unique: true
},
company_id: {
type: DataTypes.INTEGER.UNSIGNED,
},
});
const Company = sequelize.define('company', {
id: {
type: DataTypes.INTEGER.UNSIGNED,
autoIncrement: true,
primaryKey: true,
},
name: {
type: DataTypes.STRING,
},
});
User.belongsTo(Company, {
foreignKey: 'company_id', // you can use this to customize the fk, default would be like companyId
});
Company.hasMany(User);
Then when calling your model you do something like:
User.findAll({ include: Company }).then(users => console.log(users));

Answer 2

I solved the problem by using type: DataTypes.VIRTUAL in model
const { Model, DataTypes } = require('sequelize');
class User extends Model {
static init(sequelize) {
super.init({
id: {
type: DataTypes.INTEGER.UNSIGNED,
autoIncrement: true,
primaryKey: true
},
login: {
type: DataTypes.STRING(45),
unique: true
},
company_id: {
type: DataTypes.INTEGER.UNSIGNED,
},
companyname:{
type: DataTypes.VIRTUAL,
get() {
return this.Company?.get().name;
},
set(/*value*/) {
throw new Error('Do not try to set the `companyname` value!');
}
},
}, {
sequelize
})
}
static associate(models) {
this.belongsTo(Company, {
foreignKey: 'company_id',
});
}
}
module.exports = User;
to search just include the association :
User.findAll({ include: Company })
I usually create each model using 'class' in different files, but if you need, just include the code below in the #jalex19 solution
companyname:{
type: DataTypes.VIRTUAL,
get() {
return this.Company?.get().name;
},
set(/*value*/) {
throw new Error('Do not try to set the `fullName` value!');
}
},