One very useful thing you might need while working on your app is joining 2 tables.

For example you have a products table and a orders table and orders has the id of a product ordered in product_id, but the product name is in the products table.

And you want to get the name of a product that’s been ordered.

You can use the .innerJoin() method of Kysely to join the orders table with products, joining on products.id and orders.product_id:

await db
  .selectFrom('orders')
  .innerJoin(
    'products',
    'products.id',
    'orders.product_id'
  )
  .select('products.name')
  .execute()

Lessons in this unit: