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One-to-Many

A one-to-many relation means a single row on one side has many matching rows on the other.

Example​

A user has many orders.

Protocol​

"users": {
  "relations": {
    "orders": {
      "type": "otm",
      "entity": "orders",
      "prototable": "orders",
      "fkfield": "id:user_id"
    }
  }
}

The fkfield reads as: the user's id matches the order's user_id.

Query​

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

Response shape​

For otm, the related side is an array:

{
  "users": [
    {
      "id": 1,
      "name": "Ada",
      "orders": [
        { "id": 100, "total": 99, "status": "paid" },
        { "id": 101, "total": 12, "status": "open" }
      ]
    }
  ]
}

If a user has no orders, the array is empty ([]), not null.

Filtering inside the relation​

You can apply a filter or sort to the related table:

mydb.users{
  id,
  orders[status = "paid"]._desc(created_at)[0:5]{id, total}
}

This returns each user's 5 most-recent paid orders.

When to use it​

  • User → orders
  • Author → posts
  • Album → songs
  • Account → transactions