Migrating from Sequelize to Objection

I did a bit of research when I first set up my project as to what ORM I was going to use. The reason I chose to use an ORM is because I’ve always had the option to do so (and I wouldn’t say my SQL is very strong). I ended up using Sequelize on this most recent project and keep finding it difficult to work with. So I decided it was time to make a change.

I looked around a bit and it seems like people are really liking Objection as an ORM option as it allows them to also use more raw SQL if need be.

Install objection and knex

The first thing to do is to install both objection and knex.

npm install objection knex

You then need to install the package for whatever database you plan on using (i.e. mysql, postgres)

In my instance, I’m using postgres.

npm install pg

Create migration file

Add a package.json script to run the migration file

"migrate": "npx knex migrate:latest --knexfile ./db/knexfile.js"

npm run migrate

This will create a migrations file where you can add your initial database info.

How to rollback migration

knex migrate:rollback

Create seed data

Add a script to make seed file

"seed-dev": "npx knex seed:make dev --knexfile ./db/knexfile.js"

npm run make-seed-dev

This creates a seed file we can use to add sample data to our database.

To run a seed file

"seed": "npx knex seed:run --knexfile ./db/knexfile.js"

Insert the seed data

npm run seed

If you have issues with directory structure not working for your seed, take a look at your knex config file. Make sure to adjust the

seeds: {
  directory: './path-to-seeders-folder',
},

"migrate-down": "npx knex migrate:down --knexfile ./src/db/knexfile.js",

npm run migrate-down

Another problem you can run into is your knexfile not having access to your .env variables. My db configuration is nested in my src folder, requiring my dotenv declaration to specify my .env path.

import dotenv from 'dotenv';
dotenv.config({ path: 'path/to/your/env/file'});

Declaring Model Interfaces

Link