First Query

Shape the response

GraphJin treats the database schema as the source of truth. A table becomes a root field, columns become fields, and foreign-key relationships become nested selections.

query {
  products(id: $id) {
    id
    name
    owner {
      email
    }
  }
}

{ "id": 2 }

When you query by primary key, GraphJin returns a single object. When you query a collection, it returns a list.

Primary-key lookup works because GraphJin has discovered the table primary key from the database schema. For composite keys or manually mapped tables, keep table metadata explicit in config so the compiler can still distinguish single-row lookup from collection lookup.

Use aliases

GraphQL aliases let you expose API-friendly names without changing the database:

query {
  users {
    id
    fullName: full_name
  }
}

Add variables

Variables replace scalar values, not arbitrary GraphQL fragments:

query Products($ownerID: ID!, $limit: Int = 10) {
  products(
    where: { owner_id: { eq: $ownerID } }
    limit: $limit
    order_by: { id: asc }
  ) {
    id
    name
  }
}

Keep order explicit

SQL result order is undefined without order_by. Tests and production clients should ask for deterministic ordering whenever order matters.

query {
  products(limit: 5, order_by: { id: asc }) {
    id
    name
  }
}

This rule matters across dialects. A result that appears stable on PostgreSQL without order_by is still relying on undefined SQL ordering.