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

# Linked reference

> Sync: use one-way or two-way link to connect tables A and B. The link field shows the primary field — to surface other fields from A inside B, use linked reference.

# Overview

**Sync**: with [one-way link](/aitable/fields/field-types/one-way-link) or [two-way link](/aitable/fields/field-types/two-way-link), you connect tables A and B. The link field shows only the **primary field** — to surface **other fields** from A inside B, use **linked reference**.

**Aggregation**: while pulling values from A into B, the linked reference field can also aggregate them — original values, deduplicated, sum, etc.

# Basics

## Add a field

Click ➕ in the upper-right of the AI Table title bar — pick **Linked reference** under field types.

## Configure linked reference

**Pick a link field**: only **one-way / two-way link fields** in the current table — linked reference depends on a link field.

**Pick a field to reference**: only fields from the linked source table. Example: if the link field points to table A, the reference can only pick fields in A.

**Aggregation**:

| Aggregation             | Description                                |
| ----------------------- | ------------------------------------------ |
| Original                | Reference the column data directly         |
| Deduplicated            | Remove duplicates from original            |
| Sum                     | Add up the original values                 |
| Average                 | Average of the original values             |
| Max                     | Largest of the original values             |
| Min                     | Smallest of the original values            |
| Count non-empty numbers | Count of non-empty numeric values          |
| Count non-empty values  | Count of non-empty values, numeric or text |
| Count distinct          | Count after deduplication                  |
| Row count               | Count of source records                    |
| Concatenate as text     | Join displayed values with comma separator |

## Manage and edit the field

Double-click the field title or click the dropdown — copy, paste, freeze, etc.