Setup one-to-many relationship between two databases

[David Logan]

Hello all,

I am trying to setup two databases so that entries from a Child (with additional detail) that match a particular field in the Parent can be displayed automatically when opened.

The Parent contains:

• Product (text)
• Required (boolean)
• Qty (integer)

The Child contains

• Product (text, many-to-one relationship with the matching field in Parent)
• Historical date (date)
• Historical price (currency)

What I want to do is automatically display a list of historical dates and prices when I view a product in the Parent from all matching entries in the Child database

At present, I've created a one-to-many linked field in the Parent, plus a Lookup field that connects to the Product field in the Child, however I have to search for matches manually – I would like the list of matches to be displayed automatically.

Is this possible?

Thanks in advance,

David. 

[Mmm]

Основная библиотека, поле JS с кодом:

let list = entry().linksFrom('Child','Product');

let items = [];

list.forEach(e => {

    let date = moment(e.field('Historical date')).format('DD.MM.YYYY – ');

    let price = Number(e.field('Historical price')).toFixed(2) + ' €';

    items.push(date + price);

});

items.join('\n')

четверг, 29 января 2026 г. в 10:13:58 UTC+3, log...@gmail.com:

[David Logan]

Thanks @Mmm, much appreciated!

David.

[David Logan]

I've been trying this out and have a problem.

First, I needed to connect to the 'Child' library:

   let Historical_Prices = libByName("Child");

The issue is I'm getting an error, TypeError: Cannot find function forEach in object [object Library] not found. (Display_Historical.js#6)

The internet tells me this is because forEach requires an array, which means 

   list = entry().linksFrom(Historical_Prices,"Product");

must therefore not be an array.

[Mmm]

Поле JS должно быть в библиотеке "Parent" и содержать скрипт из примера выше.

>>> let Historical_Prices = libByName("Child");

В примере такой строки нет. При попытке обратиться в поле JS к объекту library – получите ошибку. 

>>> list = entry().linksFrom(Historical_Prices,"Product");

Должно быть:

let list = entry().linksFrom('Child','Product');

Где:

– "Child" имя библиотеки, а не объект библиотека;

– "Product" имя поля–связи в библиотеке "Child".

Оба имени должны быть в кавычках. Все имена нужно изменить на свои.

Необходимо дать разрешение скриптам на доступ к библиотеке "Child".

воскресенье, 1 февраля 2026 г. в 08:07:08 UTC+3, log...@gmail.com:

[Mmm]

Не забудьте включить в поле JS переключатель "Выполнять в реальном времени".

воскресенье, 1 февраля 2026 г. в 11:27:08 UTC+3, Mmm: