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# DROP DESCRIPTOR\_SOURCE

## Syntax

```sql
DROP DESCRIPTOR_SOURCE descriptor_source_name;
```

## Description

Permanently removes all [descriptors](/reference/sql-syntax/data-format-serialization.md#protocol-buffers-and-descriptors) that were imported from a [descriptor source](/reference/sql-syntax/data-format-serialization.md#protocol-buffers-and-descriptors).

{% hint style="warning" %}
**Important** `DROP DESCRIPTOR_SOURCE` cannot be undone. Use it with care!
{% endhint %}

### Arguments

#### descriptor\_source\_name

Name of the descriptor source to remove of its corresponding descriptors. If the name is case-sensitive, you must wrap it in double quotes; otherwise, the system uses the lower case name.

## Examples

#### Drop a descriptor source

The following demonstrates that when the descriptor source `pageviews` is dropped, the descriptors `pageviews.PageviewsKey` and `pageviews.Pageviews` that were extracted from it are also removed from the system:

```sh
demodb.public/demostore# LIST DESCRIPTORS;
+------------+--------------+------------+------------+-------------------------------+-------------------------------+
|  Name      |  Source Name |  Type      |  Owner     |  Created At                   |  Updated At                   |
+============+==============+============+============+===============================+===============================+
| StaffKey   | employee     | protobuf   | sysadmin   | 2024-06-04 20:46:44 +0000 UTC | 2024-06-04 20:46:44 +0000 UTC |
+------------+--------------+------------+------------+-------------------------------+-------------------------------+
| Manager    | employee     | protobuf   | sysadmin   | 2024-06-04 20:46:44 +0000 UTC | 2024-06-04 20:46:44 +0000 UTC |
+------------+--------------+------------+------------+-------------------------------+-------------------------------+
| Employee   | employee     | protobuf   | sysadmin   | 2024-06-04 20:46:44 +0000 UTC | 2024-06-04 20:46:44 +0000 UTC |
+------------+--------------+------------+------------+-------------------------------+-------------------------------+
| Address    | employee     | protobuf   | sysadmin   | 2024-06-04 20:46:44 +0000 UTC | 2024-06-04 20:46:44 +0000 UTC |
+------------+--------------+------------+------------+-------------------------------+-------------------------------+
demodb.public/demostore# DROP DESCRIPTOR_SOURCE employee;
+-------------------+------------+------------+------------------------------------------+
|  Type             |  Name      |  Command   |  Summary                                 |
+===================+============+============+==========================================+
| descriptor_source | employee   | DROP       | descriptor source "employee" has been    |
|                   |            |            | deleted                                  |
+-------------------+------------+------------+------------------------------------------+
demodb.public/demostore# LIST DESCRIPTORS;
+------------+--------------+------------+------------+-------------+-------------+
|  Name      |  Source Name |  Type      |  Owner     |  Created At |  Updated At |
+============+==============+============+============+=============+=============+
+------------+--------------+------------+------------+-------------+-------------+
```