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## Resource: Introduction

## Article: Attribute Values Introduction

## Article Link: https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-value/introduction.md

## Article Content:

# About Attribute Values

An attribute value stores the value of an [attribute definition](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-definition/introduction.md) for a specific entity. Each value references its definition and the entity it belongs to, and its type always matches the definition's `valueType`.

This API is specifically used for setting and reading attribute values. You manage them in bulk, per entity: there's no single-value get, create, update, or delete. For more information about the broader Attributes API, including how definitions and values relate and how visibility works, see [About the Bookings Attributes API](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/introduction.md).

With the Attribute Values API, you can:

- Set an entity's values in bulk with [Bulk Upsert Attribute Values](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-value/bulk-upsert-attribute-values.md), and remove them in bulk with [Bulk Delete Attribute Values](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-value/bulk-delete-attribute-values.md).
- Retrieve an entity's values, each paired with its definition, with [List Entity Attributes](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-value/list-entity-attributes.md), suitable for rendering forms or public-facing listings.
- Query and filter attribute values across the site with [Query Attribute Values](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-value/query-attribute-values.md).

## Before you begin

It's important to note the following points before starting to code:

- The caller supplies an entity's ID. This API doesn't validate that the ID refers to a real entity in another service, so make sure the entity IDs you pass refer to a resource your app owns.
- You create and update values only in bulk, per entity. There are no single-value methods.
- Visibility isn't enforced by the API. List Entity Attributes and Query Attribute Values return all values regardless of the definition's `visibility`, so filter out hidden attributes before rendering them for end users.
- The order of returned values isn't guaranteed. Sort client-side if you need a stable order.
- Each entity supports up to 50 attribute values.

## Use cases

- [Set up attributes and display values on the public site](https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/sample-flows.md)

## Terminology

- **Attribute value**: The value of an attribute definition for a specific entity.
- **Attribute definition**: A typed custom property (string, number, or boolean) with a name, optional configuration, and a default value. Defined once per site.
- **Entity**: Any item that has attribute values. The entity's identity is supplied by the caller via `entityId`; this API doesn't own or validate it.


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