---
schema_version: "1"
id: bad8fdd3185c7c30c5fcaee3761dc60193e66a73468e60e6ead1665d9d11929c
title: Get a List of Objects If Metadata Has Changed
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locale: en-us
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content_type: documentation
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  - REST API Developer Guide
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---

# Get a List of Objects If Metadata Has Changed

Use the Describe Global resource and the `If-Modified-Since` HTTP header to determine if an object’s metadata has changed.

You can include the `If-Modified-Since` header with a date in `EEE, dd MMM yyyy HH:mm:ss z` format when you use the [Describe Global](https://developer.salesforce.com/docs/platform/api-rest/resources/resources-describeglobal.md) resource. If you do, response metadata is returned only if an available object’s metadata has changed since the provided date. If no metadata has been modified since the provided date, a `304 Not Modified` status code is returned with no response body.

The following example assumes that no changes have been made to objects after March 23, 2015.

If changes to an object were made after March 23, 2015, the response body contains metadata for all available objects. For an example, see [Get a List of Objects](https://developer.salesforce.com/docs/platform/api-rest/guide/dome-describeglobal.md).

## Example Describe Global request

`/services/data/v68.0/sobjects`

## Example `If-Modified-Since` header used with request

`If-Modified-Since: Tue, 23 Mar 2015 00:00:00 GMT`

## Example response body

No response body returned

## Example response status code

```nolang
HTTP/1.1 304 Not Modified
Date: Wed, 25 Jul 2015 00:05:46 GMT
```