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Description

Why Would You Use Description on Dataset?​

Adding a description and related link to a dataset can provide important information about the data, such as its source, collection methods, and potential uses. This can help others understand the context of the data and how it may be relevant to their own work or research. Including a related link can also provide access to additional resources or related datasets, further enriching the information available to users.

Goal Of This Guide​

This guide will show you how to

  • Read dataset description: read a description of a dataset.
  • Read column description: read a description of columns of a dataset`.
  • Add dataset description: add a description and a link to dataset.
  • Add column description: add a description to a column of a dataset.

Prerequisites​

For this tutorial, you need to deploy DataHub Quickstart and ingest sample data. For detailed steps, please refer to Datahub Quickstart Guide.

note

Before adding a description, you need to ensure the targeted dataset is 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 sample ingestion.

In this example, we will add a description to user_name column of a dataset fct_users_deleted.

Read Description on Dataset​

query {
  dataset(urn: "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)") {
    properties {
      description
    }
  }
}

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

{
  "data": {
    "dataset": {
      "properties": {
        "description": "table containing all the users deleted on a single day"
      }
    }
  },
  "extensions": {}
}

Read Description on Columns​

query {
  dataset(urn: "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)") {
    schemaMetadata {
      fields {
        fieldPath
        description
      }
    }
  }
}

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

{
  "data": {
    "dataset": {
      "schemaMetadata": {
        "fields": [
          {
            "fieldPath": "user_name",
            "description": "Name of the user who was deleted"
          },
          ...
          {
            "fieldPath": "deletion_reason",
            "description": "Why the user chose to deactivate"
          }
        ]
      }
    }
  },
  "extensions": {}
}

Add Description on Dataset​

curl --location --request POST 'http://localhost:8080/api/graphql' \
--header 'Authorization: Bearer <my-access-token>' \
--header 'Content-Type: application/json' \
--data-raw '{
  "query": "mutation updateDataset { updateDataset( urn:\"urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_created,PROD)\", input: { editableProperties: { description: \"## The Real Estate Sales Dataset\nThis is a really important Dataset that contains all the relevant information about sales that have happened organized by address.\n\" } institutionalMemory: { elements: { author: \"urn:li:corpuser:jdoe\", url: \"https://wikipedia.com/real_estate\", description: \"This is the definition of what real estate means\" } } } ) { urn } }",
  "variables": {}
}'

Expected Response:

{
  "data": {
    "updateDataset": {
      "urn": "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_created,PROD)"
    }
  },
  "extensions": {}
}

Expected Outcomes of Adding Description on Dataset​

You can now see the description is added to fct_users_deleted.

Add Description on Column​

mutation updateDescription {
  updateDescription(
    input: {
      description: "Name of the user who was deleted. This description is updated via GrpahQL.",
      resourceUrn:"urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)",
      subResource: "user_name",
      subResourceType:DATASET_FIELD
    }
  )
}

Note that you can use general markdown in description. For example, you can do the following.

mutation updateDescription {
  updateDescription(
    input: {
      description: """
      ### User Name
      The `user_name` column is a primary key column that contains the name of the user who was deleted.
      """,
      resourceUrn:"urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)",
      subResource: "user_name",
      subResourceType:DATASET_FIELD
    }
  )
}

updateDescription currently only supports Dataset Schema Fields, Containers. For more information about the updateDescription mutation, please refer to updateLineage.

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

{
  "data": {
    "updateDescription": true
  },
  "extensions": {}
}

Expected Outcomes of Adding Description on Column​

You can now see column description is added to user_name column of fct_users_deleted.