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

# Rollup

> Aggregate values from linked records, such as sum, count, average, maximum, and minimum.

Rollup fields calculate statistics from multiple linked records. A Rollup field usually starts from an existing **Link** field, selects a target field from linked records, and calculates the result with a chosen function.

## Use Cases

| Scenario       | Good for                                                           |
| -------------- | ------------------------------------------------------------------ |
| Order amount   | Roll up prices from order line items to calculate the order total  |
| Task progress  | Count linked tasks, completed tasks, or average ratings            |
| Customer value | Roll up total spend or order count from customer orders            |
| Tag cleanup    | Combine tags, participants, or source channels from linked records |

## Create and Configure

<Steps>
  <Step title="Create a link relationship">
    Before creating a Rollup field, create a **Link** field.
  </Step>

  <Step title="Choose the field type">
    Click `+` in the table header to add a field and choose **Rollup**.
  </Step>

  <Step title="Choose the link field and target field">
    Choose the link field that provides the data source, then choose the target field to calculate.
  </Step>

  <Step title="Choose the rollup function">
    Choose a function based on the target field type, such as sum, count, average, maximum, or minimum.
  </Step>
</Steps>

## Formatting and Display

Rollup results can usually use formatting and interactive display settings:

* **Formatting**: Set decimal precision, currency symbols, or percentages.
* **Interactive display**: Show number results as bars, rings, or other display styles.

See [formatting](/en/basic/field/common/formatter) and [interactive display](/en/basic/field/common/show-as) for details.

## Common Uses

* **Bookstore order totals**: In an `Orders` table, use the `Selected books` link field to roll up the `Price` field from the `Books` table. Choose **SUM** to calculate the order total.
* **Project task statistics**: In a `Projects` table, count linked tasks or calculate task completion rate.
* **Customer spending totals**: In a `Customers` table, roll up related order amounts to see each customer's total spend.

## Supported Rollup Formulas

| Formula name   | Explanation                                                      |
| -------------- | ---------------------------------------------------------------- |
| COUNTALL       | Counts all values, including text values and blanks              |
| COUNTA         | Counts non-empty values                                          |
| COUNT          | Counts numeric items                                             |
| SUM            | Calculates the sum of all numeric values                         |
| MAX            | Returns the largest numeric value                                |
| MIN            | Returns the smallest numeric value                               |
| AND            | Returns true if all values are true                              |
| OR             | Returns true if any value is true                                |
| XOR            | Returns true if an odd number of values are true                 |
| ARRAY\_JOIN    | Joins all values in an array into a string                       |
| ARRAY\_UNIQUE  | Removes duplicate values and returns an array with unique values |
| ARRAY\_COMPACT | Removes empty values and returns a new array                     |
| CONCATENATE    | Joins multiple values into a string                              |

## Notes

* **Dynamic updates**: Rollup fields calculate in real time. If source data or link relationships change, the rollup result refreshes.
* **Data type limits**: Some functions only work with specific field types. For example, **SUM** only works with number fields. If you choose a text field, Teable does not offer sum as an option.
* **Performance**: Many rollup fields can affect performance, especially when they involve many records. Plan link relationships carefully and review rollup settings from time to time.