---
title: "Assign the Source of an Application"
slug: "assign-the-source-of-an-application"
updated: 2026-05-14T18:34:32Z
published: 2026-05-14T18:34:32Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://knowledge.technolutions.net/llms.txt
> Use this file to discover all available pages before exploring further.

# Assign the Source of an Application

It’s useful to differentiate between application sources—that is, whether they are Slate-hosted or from an external source—for reporting. In Slate, you can create [rules](/v1/docs/rules-overview) that automate this process.

As an example, your institution might plan to receive three sources of external applications, plus the default Slate-hosted application.

To do this, we’ll create an *Application Source*[exclusivity group](/v1/docs/exclusivity-groups) of rules that check, in order, whether the incoming application matches any of these import types:

- First, *The Common Application*
- Next, *Questbridge*
- Third, *Universal College Application*
- Finally, if the application doesn’t satisfy any of the above, the application is determined to have been a [Slate-hosted application](/v1/docs/introduction-to-the-slate-hosted-application).

Your institution may receive applications from different sources; these rules can be configured for any external application source.

## Before you begin

These three imported applications each have a **unique field**, and are listed as prompt options within the **application source field**alongside the Slate-hosted application.

To configure the rules described in this article, for each application source, your database must have:

- **Unique fields**: There must be one [unique ID](/v1/docs/unique-for-merging) for each application type (excluding the Slate-hosted application).
- **Application source field**: This custom, application-scoped, prompt-based field includes a prompt for each application type.

## Assigning external application sources

These rules set the application source for **external application sources**. As an English sentence, the rule for Common Applications would read:*If the application-scoped external application ID field exists for an application, then set the Application Source to Common Application.*

#### Creating the rule

To create this rule:

1. Go to **Database** → **Rules.**
2. Select **New Rule**.
3. Configure the following settings:
  - **Name:** Enter a name for the external application source rule, like `Set <Application name> source`.
  - **Type:** Configurable Joins
  - **Category:**Records
  - **Base:** Application
  - **Rule Type:** Field
  - **Trigger:** Upon Application Submission Only 💡 Because the application source will never change, we configure these rules to use the *Upon Application Submission Only*trigger. The rule only runs at the time of application submission.
  - **Folder:** Keep rules organized by placing them in an existing folder, or select *Other*and enter `Application Source` to create a new one.
  - **Exclusivity Group:** Select *Other*and enter `Application Source` to create an [exclusivity group](/v1/docs/exclusivity-groups) for the rules created in this article.
  - **Non-deterministic:** Rule is deterministic and has an exclusive priority
  - **Priority:** This establishes the order in which the rules in the exclusivity group are evaluated. Enter a low number for the first rule, like `5`. Increase the number by five for each application source rule.
4. Select **Save**.

#### Configuring rule filters

To select only records from the external application:

1. Select **Subquery Filter.**
2. Configure the following settings:
  - **Name:**Enter a name for the subquery filter, like `<Application name> ID Exists`
  - **Type:**Dependent subquery
  - **Aggregate:**Exists
  - **Filters:**Select *Filter*. Configure the following settings:
    1. Select the **external application ID field**you [created earlier](/v1/docs/assign-the-source-of-an-application#before-you-begin).
    2. Select **Continue**.
    3. Leave the filter selection as **IN LIST**.
    4. Select **Save.**

![](https://cdn.us.document360.io/cd8ea7a6-07f3-4846-a554-627ac016d3e3/Images/Documentation/Subquery filter - Common App ID Exists.png)

An example subquery filter for the existence of a Common Application ID
3. Select **Save.**

#### Configuring the rule action

1. In the Action section, configure the following settings:
  - **Field**: Select the Application Source field you [created earlier](/v1/docs/assign-the-source-of-an-application#before-you-begin).
  - **Action**: Replace Values
  - **Prompt**: Enter `Common Application`

![](https://cdn.us.document360.io/cd8ea7a6-07f3-4846-a554-627ac016d3e3/Images/Documentation/Rule Action - Common App.png)
2. Select **Save.**

#### Repeat

For as many external application sources as you want to evaluate for assignment, add a new rule following the preceding steps.

> [!WARNING]
> 📝 Increment the rule priority number by five with each external application source.

## Assigning Slate Application sources (default rule)

This rule sets the application source for **Slate-hosted applications.** As an English sentence, this rule would read: *If an application record does not meet the filter criteria for the previous rules, then set the Application Source to Slate Application.*

1. Go to **Database → Rules**.
2. Select **New Rule**.
3. Configure the following settings:
  - **Name**: Set Slate-hosted application source
  - **Base**: Applications
  - **Type**: Field
  - **Trigger**: Upon Submission Only 💡 Because the application source will never change, we configure these rules to use the *Upon Application Submission Only*trigger. The rule only runs at the time of application submission.
  - **Folder**: Application Source
  - **Exclusivity Group**: Application Source
  - **Non-deterministic**: Rule is deterministic and has an exclusive priority.
  - **Priority:**Enter a priority number larger than all of those of the preceding rules. If, for example, you made four external source assignment rules incrementing by `5`, enter `25` for this rule’s priority.
4. Select **Save**.

#### Configuring rule filters

Because this source will serve as a catch-all and be given to any applications that do not meet the prior rules, there is no need to include a filter.

#### Configure the rule action

1. In the Action section, configure the following settings:
  - **Field**: Application Source
  - **Action**: Replace Values
  - **Prompt**: Slate Application
2. Select **Save.**