datahub/docs/api/tutorials/reading-owners.md

# Reading Owners On Datasets/Columns

## Why Would You Read Owners?

Assigning an owner to an entity helps to establish accountability for the metadata and collaborating as a team.
If there are any issues or questions about the data, the designated owner can serve as a reliable point of contact.

### Goal Of This Guide

This guide will show you how to read owners attached to a dataset `SampleHiveDataset`.

## Prerequisites

For this tutorial, you need to deploy DataHub Quickstart and ingest sample data.
For detailed steps, please refer to [Datahub Quickstart Guide](/docs/quickstart.md).

:::note
Before reading owners, you need to ensure the targeted dataset and the owner are already present in your datahub.
If you attempt to manipulate entities that do not exist, your operation will fail.
In this guide, we will be using data from a sample ingestion.
:::

## Read Owners With GraphQL

:::note
Please note that there are two available endpoints (`:8000`, `:9002`) to access `graphql`.
For more information about the differences between these endpoints, please refer to [DataHub Metadata Service](../../../metadata-service/README.md#graphql-api)
:::

### GraphQL Explorer

GraphQL Explorer is the fastest way to experiment with GraphQL without any dependencies.
Navigate to GraphQL Explorer (`http://localhost:9002/api/graphiql`) and run the following query.

```json
query {
  dataset(urn: "urn:li:dataset:(urn:li:dataPlatform:hive,SampleHiveDataset,PROD)") {
    ownership {
      owners {
        owner {
          ... on CorpUser {
            urn
            type
          }
          ... on CorpGroup {
            urn
            type
          }
        }
      }
    }
  }
}
```

If you see the following response, the operation was successful:

```python
{
  "data": {
    "dataset": {
      "ownership": {
        "owners": [
          {
            "owner": {
              "urn": "urn:li:corpuser:jdoe",
              "type": "CORP_USER"
            }
          },
          {
            "owner": {
              "urn": "urn:li:corpuser:datahub",
              "type": "CORP_USER"
            }
          }
        ]
      }
    }
  },
  "extensions": {}
}
```

### CURL

With CURL, you need to provide tokens. To generate a token, please refer to [Access Token Management](/docs/api/graphql/token-management.md).
With `accessToken`, you can run the following command.

```shell
curl --location --request POST 'http://localhost:8080/api/graphql' \
--header 'Authorization: Bearer <my-access-token>' \
--header 'Content-Type: application/json' \
--data-raw '{ "query": "{ dataset(urn: \"urn:li:dataset:(urn:li:dataPlatform:hive,SampleHiveDataset,PROD)\") { ownership { owners { owner { ... on CorpUser { urn type } ... on CorpGroup { urn type } } } } } }", "variables":{}}'
```

Expected Response:

```json
{
  "data": {
    "dataset": {
      "ownership": {
        "owners": [
          { "owner": { "urn": "urn:li:corpuser:jdoe", "type": "CORP_USER" } },
          { "owner": { "urn": "urn:li:corpuser:datahub", "type": "CORP_USER" } }
        ]
      }
    }
  },
  "extensions": {}
}
```

## Read Owners With Python SDK

The following code reads owners attached to a dataset `fct_users_created`.

> Coming Soon!

We're using the `MetdataChangeProposalWrapper` to change entities in this example.
For more information about the `MetadataChangeProposal`, please refer to [MetadataChangeProposal & MetadataChangeLog Events](/docs/advanced/mcp-mcl.md)