# Manage create and duplicate functionalities

<p class="callout danger">This action requires the "**update documents"** permission. </p>

On the document's page, it is possible to define "**rules**", that determine what values are written into what fields. (eg. *a date field is, by default, set to today's date on the 'create' form*).

####  

#### Create

Defined in the **"Create rules"** field.

- Here, you can define what values fields are given, when the **"create"** form is loaded
- eg. the **date fields** (date\_vat, date\_paid...) can be set to have the default value of "**new\_date**" when the form loads.

![image.png](https://how-to-erp.dewesoft.com/uploads/images/gallery/2025-02/scaled-1680-/36Rimage.png)

<p class="callout info">At current, the **rules** need to be **defined** in the **JSON format:** { "field\_name": "field\_value" }.</p>

#### Update

Defined in the **"Duplicate rules"** field.

- The duplicate rules are used, when duplicating a row (eg. products, serials...).
- These rules define which values are copied from the "original" into the **"duplicate"** form.

![image.png](https://how-to-erp.dewesoft.com/uploads/images/gallery/2025-02/scaled-1680-/RFwimage.png)

<p class="callout info">At current, the **rules** need to be **defined** in the **JSON format:** { "fields": \[ {"field\_name": "field\_value"},... \]}</p>