To

Definition

A relationship is always between the outer class where it is defined and another class, specified in the property to.

For example, the relationship lives_in goes from person to a country.

Usage

Let's say we have the following tables: PERSON(id, name, country_id) and COUNTRY(id, name).

In this case the relationship lives_in is going to be defined inside kb.Person and contains the property to: kb.Country.

import db.postgres.world.public.PERSON

kb {

    class Person {
        name.en: "Person"
        sql: "${PERSON.id}"

        relationship lives_in {
            display_name: "lives in"
            to: kb.Country
            
            sql: "${PERSON.country_id}"
        }

        ...
    }
}