When building forms in Jodoo, you may encounter two similar but fundamentally different field types: Subform and Related Subform. Both allow you to display and manage data within a main form, but they serve different purposes. This article will walk you through the differences between them.
What Are Subform and Related Form?
Subform
A Subform is a table-like section embedded directly within a main form. Data entered in a subform is always stored as part of the main record. Subform data does not exist independently—if you delete the main record, all its subform data is deleted as well.
Example:
In an Employee Management System, each employee may have several transfer records (job changes). These transfer records are only useful when viewed together with the employee’s main information—they don’t need to be managed or referenced on their own. In this case, using a subform is the best choice.
In short: If your data is always part of the main record and doesn’t need to be used independently, use a subform.
Related Form
A Related Form is a way to display the related form in a tabular format within the master form. This allows users to enter, view, export, and print data from both the master and related forms. Behind the scenes, the related form is an independent data form: its records exist separately from the master form, can be referenced by other forms, and have their own permissions, workflows, and business logic.
Example:
In an Order Management System, you have an order form and an order details form. The order details need to be viewed with the order, but sometimes you also need to process a single order detail separately—for example, shipping part of an order, or combining items from different orders for shipment. In this case, use a Related Form. Each order detail is a separate record that can be managed independently or referenced in other forms such as shipping or payment.
When Should You Use Each?
Here’s a quick comparison to help you decide:
Feature | Subform | Related Form (Linked Subtable) |
Best for | Data that only matters inside the main form | Data that needs to be reused or referenced elsewhere |
Data independence | No—always tied to the main form | Yes—can exist and be managed on its own |
Complexity | Simple operations (calculations, summaries) | Complex processes (partial shipments, workflows) |
Data volume | Small datasets (up to ~200 rows) | Large datasets (hundreds or thousands of rows) |
When using Subform and Related Form fields in Jodoo, their configuration approaches are quite different:
Subform: All configuration—such as adding fields, setting rules, and managing permissions—is done directly within the main form. The subform acts as an embedded section of the main form, and its settings are controlled entirely from there.
Related Form: This field serves as a gateway to a separate, related form. You must first set up and configure the related form itself (defining its fields, rules, and permissions). After that, you add a Related Form field to your master form, which connects to the related Form. The final behavior and appearance of the related form are determined by a combination of settings from both the related table and the related subform field in the main form.
Below is a comparison of their configuration in common scenarios:
Configuration Item | Subform | Related Form |
Field Settings | Add fields to a subform, set validation, and default values directly in the main form. | Configure in the related form. |
Permission Settings | Configure in the main form. | Determined by both the permission on the related form and the Related Form field settings. |
Duplicate Value Check | Configure in the main form. | Configure both in the Related Form field (in the master form) and in the related form. |
Data Linkage | Configure the linkage between fields of a subform or the whole subform in the main form. | Field linkage is set in the related form; whole-table linkage requires a custom button. |
Main Record Deletion | Subform data is embedded in the main record and will be deleted together automatically. | Related form data is stored separately; use automation to cascade delete or clear related data. |
Main Record Update | If subform data depends on main data (e.g., formulas or linkages), updates happen automatically. | If related table data is filled from the main form, it will not update automatically; use automation for cascading updates. |
Formula Reference | Subform formulas can directly reference main form fields. | In the related form, use reference fields and filling rules to bring in main form values for formulas. |
Visibility Rules | Configure in the main form. | Configure in the related form. To control visibility based on main form fields, fill in the main data into related fields first. |
Subform Data Affecting Main Validation | Set validation in the main form to check all subform entries before submission. | Set validation in the related table; this will affect the main form submission when filling it out together. |
Data Filtering | When using "Select Data" in a subform, you can filter based on the main form content. | In the related table, set filtering conditions using reference fields or filled main form values. |
Permission Settings
Subform
Operation Permissions: Set directly in the main form. You can control whether users can edit, delete, or add subform entries.
Data Permissions: Always follow the permissions of the main form record. Subform entries do not have independent data permissions, and you cannot set permissions for individual subform rows separately.
Related Form
Operation Permissions: Permissions are elevated from the main form field level to the related table (independent form) level.
Final Permissions: A user’s effective permissions are determined by the intersection of:
The related form’s permission groups and data management settings.
The display and data operation settings of the Related Form field in the main form.
This means both the related form’s permissions and the Related Form’s settings in the main form affect what users can see and do.
Formula Settings
Subform
When editing a formula in a Subform, you may need to reference values from fields in the main form. What you need to do is select the required main form field directly from the variable list.
Related Form
If you are working with a Related Form, you need to first use the Fill Rules of the Related Form field to fill the value of the main form field into a corresponding field in the related form. Then, use that filled field in the formula.