> ## 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.

# Single Value and Multiple Values

> Explains whether a field cell stores one value or a group of values.

Single value and multiple values describe whether a cell stores one value or a group of values. After you understand this concept, it is easier to see why links, lookups, rollups, and formulas may return multiple results.

## Basic Concepts

| Type            | Description                                    | Example                                               |
| --------------- | ---------------------------------------------- | ----------------------------------------------------- |
| Single value    | One definite piece of information              | "today's date", "John's phone number"                 |
| Multiple values | A group of values, also understood as an array | "all dates this month", "all of John's phone numbers" |

## Default Single and Multiple Value States

| Field type                                                                          | Default state |
| ----------------------------------------------------------------------------------- | ------------- |
| Single line text, long text                                                         | Single        |
| Single select, checkbox, date, number, rating                                       | Single        |
| Created time, last modified time, created by, last modified by, auto number, button | Single        |
| Multiple select, attachment                                                         | Multiple      |
| User                                                                                | Optional      |
| Link                                                                                | Optional      |
| Formula, rollup                                                                     | Dynamic       |

Here, "default state" means the field's common state on its own. **Optional** means you can decide whether the field is single-value or multiple-value through field settings. **Dynamic** means the result depends on formula logic, rollup functions, and whether referenced fields are multiple-value fields. After a value passes through a link, lookup, rollup, or formula reference, its state may change.

## State Changes from Links and References

* **Link fields**: If a link field is multiple-value, fields referenced through that link may also become multiple-value. For example, if one task can be assigned to several employees, looking up employee phone numbers through that link may return several phone numbers.
* **Formulas and rollups**: Formulas and rollups are often single-value, but they may become multiple-value when they reference multiple-value fields.

### Example

Suppose you manage a company in Teable with two tables: `Employee Information` and `Project Tasks`.

**Employee Information table**

| Name | Phone  | Email                                       | Tasks          |
| ---- | ------ | ------------------------------------------- | -------------- |
| John | 123456 | [john@company.com](mailto:john@company.com) | Task 1, Task 2 |
| Mary | 789012 | [mary@company.com](mailto:mary@company.com) | Task 3         |

**Project Tasks table**

| Task name | Assignee | Due date   | Progress |
| --------- | -------- | ---------- | -------- |
| Task 1    | John     | 2023-11-20 | 50%      |
| Task 2    | John     | 2023-12-01 | 30%      |
| Task 3    | Mary     | 2023-11-15 | 80%      |

In this example:

* The "Tasks" field in the **Employee Information** table is multiple-value because one employee can be responsible for several tasks.
* The "Assignee" field in the **Project Tasks** table is single-value because each task has one assignee.

When you create a new task in the "Project Tasks" table and assign it to an employee, that employee's "Tasks" field in the "Employee Information" table updates to include all assigned tasks.

### Number Mini Charts

Number fields sometimes display multiple lines or bars instead of one number. This usually means the field has become multiple-value, often through a link, lookup, rollup, or formula reference.