Relation Projections

When you put a relation name inside a projection, ONQL embeds the related rows. The shape of the embedded value depends on the relation type.

otm and mtm → array

mydb.users{name, orders{id, total}}

{
  "users": [
    { "name": "Ada", "orders": [{ "id": 1, "total": 99 }] }
  ]
}

oto and mto → object

mydb.users{name, profile{bio}}

{
  "users": [
    { "name": "Ada", "profile": { "bio": "..." } }
  ]
}

If the related row doesn't exist, the value is null.

Filtering inside

mydb.users{name, orders[status = "paid"]{id, total}}

The filter applies inside each user's orders.

Sorting inside

mydb.users{name, orders._desc(created_at)[0:5]{id, total}}

Each user gets their 5 most recent orders.

Aggregating inside

mydb.users{name, orders._sum(total)}

orders becomes the sum, not the array.

Aliases? No.

ONQL doesn't currently rename projection keys. The key in the output is always the relation or column name from the protocol. If you need a different name, define a second entity in the protocol with the alias you want.