how to use ternary operatiion in sequelize join statement

How to Use Ternary Operation in Sequelize Join Statement

If you are working with Sequelize, you may come across a situation where you need to use a ternary operation in a join statement. A ternary operation is a shorthand for an if-else statement and can be used to simplify your code.

Let's say you have two tables, 'users' and 'posts', and you want to join them based on a condition. You can use a ternary operation in the 'on' clause of the join statement to achieve this.

const Sequelize = require('sequelize');
const sequelize = new Sequelize('database', 'username', 'password', {
  host: 'localhost',
  dialect: 'mysql'
});

const User = sequelize.define('user', {
  username: Sequelize.STRING,
  isAdmin: Sequelize.BOOLEAN
});

const Post = sequelize.define('post', {
  title: Sequelize.STRING,
  content: Sequelize.TEXT,
  published: Sequelize.BOOLEAN
});

User.hasMany(Post);
Post.belongsTo(User);

const isAdmin = true;

Post.findAll({
  include: [{
    model: User,
    attributes: ['username'],
    on: {
      [Sequelize.Op.and]: isAdmin ? { isAdmin: true } : {}
    }
  }]
}).then(posts => {
  console.log(posts);
});

The above code uses a ternary operation in the 'on' clause of the join statement to include only those posts that belong to an admin user. If 'isAdmin' is true, the condition '{ isAdmin: true }' is added to the 'and' operator. Otherwise, an empty object is added.

You can also use a ternary operation in the 'attributes' clause of the include statement to select certain attributes based on a condition.

const isPublished = true;

User.findAll({
  include: [{
    model: Post,
    attributes: isPublished ? ['title', 'content'] : ['title']
  }]
}).then(users => {
  console.log(users);
});

The above code uses a ternary operation in the 'attributes' clause of the include statement to select either ['title', 'content'] or ['title'] based on the value of 'isPublished'.

Using ternary operations in Sequelize join statements can help simplify your code and make it more readable. However, be sure to use them judiciously and only when they enhance the clarity of your code.