# Build a reference number from other fields

Combine two fields into one — vendor code plus invoice number into a single reference, say — the moment a document is filed, with a Content Capture trigger and a Merge Field Values action, so the combined value exists for searches, file names, and exports without anyone typing it.

Product: content-central · Versions: 7.8+ · Audience: catalog-administrator · Time: 15 minutes · Last verified: 2026-09-05

Canonical: https://help.ademero.com/content-central/workflow/build-a-reference-number-from-other-fields

**When you're done, every newly filed document gets a reference field filled from two other fields — `ACME-10442` from a vendor code and an invoice number — automatically, consistently, and searchable the moment it exists.**

```plan
scope: document-type
trigger: Content Capture › Content Captured in this Document Type | Field Evaluation: Selected Field Has Value · Field: Invoice Number
action: Content - Merge Field Values | Field to Match: Vendor Code · Field to Merge: Invoice Number · Separator Character: - · result written to the merge field
rule: "Filed with invoice number → build reference", enabled
```

## Build the trigger

1. Go to **Administration** > **Catalogs & Document Types**, pick the **Catalog** and **Document Type**, click the **Workflow** tile, then **Triggers** > **New Trigger**.

2. **Type:** `Content Capture` and `Content Captured in this Document Type`. **Trigger Name:** `Filed with an invoice number`.

3. **Field Evaluation:** `Selected Field Has Value`, **Field:** the invoice number field — no point merging an empty value.

4. Click **Save**.

## Build the action

1. Click **Actions** > **New Action**. **Type:** `Content - Merge Field Values`. **Action Name:** `Build reference number`.

2. Set **Field to Match** to the first source field and **Field to Merge** to the second. The lists only offer fields of this document type; the second list hides whatever you chose in the first.

3. **Separator Character:** choose how the two values are joined — a single character such as `-`, a space, or no separator.

4. Click **Save**.

> **NOTE:** Check which field receives the merged result on the action form before saving — the form names it explicitly. If your document type doesn't yet have a field for the result, add a text field under the **Fields** tile first, then come back.

## Wire the rule

1. Click **Rules** > **New Rule**. **Rule Name:** `Filed with invoice number → build reference`.

2. **Add Trigger:** `Filed with an invoice number`. **Add Action:** `Build reference number`. **Apply**.

## Test it

1. File one document with a vendor code and an invoice number.

2. Open its properties.

**What you should see:** the reference field holding the two values joined by your separator, and the rule in **View History**. Search for the combined value to confirm it's indexed.

## Variations

| Want this instead | Change this |
| --- | --- |
| Rebuild the reference if someone edits either source field | Two **Content Field Values** › **Field Value Updated in this Document Type** triggers (one per source field), each in a rule with the same action |
| Use the reference in the stored file name or folder | That's the document type's own naming rules: [Folder and file building](/content-central/administration/folder-and-file-building) |
| Write a fixed prefix instead of a second field | **Content - Update Field** with the literal value into the reference field first, then merge |
| Combine *global* fields shared across types | **Content - Combine Global-Field Values** |
| Produce a start–end range string from two numbers | **Content - Calculate Field-Value Range** |
| A summary of every field's name and value in a memo field | **Content - Create Field Name and Value Summary** |

## What's next

- [Stamp today's date when a status changes](https://help.ademero.com/content-central/workflow/stamp-todays-date-when-a-status-changes)
- [Folder and file building](https://help.ademero.com/content-central/administration/folder-and-file-building)
- [Look up vendor details from your ERP when an invoice arrives](https://help.ademero.com/content-central/workflow/look-up-vendor-details-when-an-invoice-arrives)