sequelize express framework many to many association not working

can some one help in the issue Model1 is not associated to Model 2 in many to many relationship

I have a Depts Model

module.exports = function (sequelize, DataTypes) { var Depts = sequelize.define(‘Depts’, { Id: { type: DataTypes.INTEGER, allowNull: false, primaryKey: true }, Name: { type: DataTypes.STRING, allowNull: false } }, { classMethods: { associate: function (models) {

                Depts.hasMany(models.Employees, {
                    foreignKey: 'DeptId'
                });
                Depts.belongsToMany(models.Students, {
                    foreignKey: 'DeptId',
                    through: models.StudentDepts,
                    unique: false
                });
            }

        },
        timestamps: false
    },
    {
        tableName: 'Depts'
    }

);
return Depts;

};

Student Models as

module.exports = function (sequelize, DataTypes) { var Students = sequelize.define(‘Students’, { Id: { type: DataTypes.INTEGER, allowNull: false, references: { model: ‘Students’, key: ‘Id’ } }, Name: { type: ‘NCHAR’, allowNull: true } }, { timestamps: false }, { tableName: ‘Students’ }, { classMethods: { associate: function (models) { Students.belongsToMany(models.Depts, { foreignKey: ‘StudentId’, through: models.StudentDepts, unique: false }); } } } ); return Students; };

Employees Models as module.exports = function (sequelize, DataTypes) { var Employees = sequelize.define(‘Employees’, { Id: { type: DataTypes.INTEGER, allowNull: false, primaryKey: true }, Name: { type: DataTypes.STRING, allowNull: false }, DeptId: { type: DataTypes.INTEGER, allowNull: false, } }, { classMethods: { associate: function (models) { Employees.belongsTo(models.Depts); } }, timestamps: false },

    {
        tableName: 'Employees'
    }
);

return Employees

};

Many to Many Relation here in StudentDepts Model as module.exports = function(sequelize, DataTypes) { var StudentDepts = sequelize.define(‘StudentDepts’, { StudentId: { type: DataTypes.INTEGER, allowNull: false, references: { model: ‘Students’, key: ‘Id’ } }, DeptId: { type: DataTypes.INTEGER, allowNull: false, references: { model: ‘Depts’, key: ‘Id’ } } }, { timestamps: false }, { tableName: ‘StudentDepts’ });

return StudentDepts;

};

Models are initialized by indesx.js which is

var fs = require(“fs”); var path = require(“path”); var Sequelize = require(“sequelize”); var config = require(‘…/db_config’);

var sequelize = new Sequelize(config.database, config.username, config.password, { host: config.host, dialect: config.dialect, dialectOptions: { instanceName: config.instanceName }, pool: { max: config.max, min: config.min, idle: config.idle }, });

var db = {};

fs.readdirSync(__dirname) .filter(function (file) { return (file.indexOf(“.”) !== 0) && (file !== “index.js”); }) .forEach(function (file) { var model = sequelize.import(path.join(__dirname, file)); db[model.name] = model; });

Object.keys(db).forEach(function (modelName) { if (“associate” in db[modelName]) { db[modelName].associate(db); } });

db.sequelize = sequelize; db.Sequelize = Sequelize;

module.exports = db;

Now the issue is when I run

models.Students.findAll({ raw: true, include: models.Depts }).then(function (data) { console.log(data); });

this works fine

but when I run

models.Depts.findAll({ raw: true, include: models.Students }).then(function (data) { console.log(data); });

This throws the error of Depts is not associated to Students!

Also how to give more than one association in classMethods ?

currently I am doing

classMethods: { associate: function (models) {

                Depts.hasMany(models.Employees, {
                    foreignKey: 'DeptId'
                });
                Depts.belongsToMany(models.Students, {
                    foreignKey: 'DeptId',
                    through: models.StudentDepts,
                    unique: false
                });
            }

        },

[janmeier]

var Students = sequelize.define('Students', {
        Id: {
            type: DataTypes.INTEGER,
            allowNull: false,
            references: {
                model: 'Students',
                key: 'Id'
            }
        },
        Name: {
            type: 'NCHAR',
            allowNull: true
        }
    },
        { timestamps: false },
        { tableName: 'Students' },
        {
            classMethods: {
                associate: function (models) {
                    Students.belongsToMany(models.Depts,
                        { foreignKey: 'StudentId', through: models.StudentDepts, unique: false });
                }
            }
        }
    );

You are passing 4 objects to define, instead of two, putting each option into its own object - all options should be in the same object…

[vaibhavramteke787]

Thanks… that worked like a charm 😃