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Data Lineage
Why Would You Use Lineage?
Data lineage is used to capture data dependencies within an organization. It allows you to track the inputs from which a data asset is derived, along with the data assets that depend on it downstream.
For more information about data lineage, refer to About DataHub Lineage.
Goal Of This Guide
This guide will show you how to
- Add lineage between datasets.
- Add column-level lineage between datasets.
- Read lineage.
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 lineage, 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. :::
Add Lineage
mutation updateLineage {
updateLineage(
input: {
edgesToAdd: [
{
downstreamUrn: "urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD)"
upstreamUrn: "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)"
}
]
edgesToRemove: []
}
)
}
Note that you can create a list of edges. For example, if you want to assign multiple upstream entities to a downstream entity, you can do the following.
mutation updateLineage {
updateLineage(
input: {
edgesToAdd: [
{
downstreamUrn: "urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD)"
upstreamUrn: "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)"
}
{
downstreamUrn: "urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD)"
upstreamUrn: "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_created,PROD)"
}
]
edgesToRemove: []
}
)
}
For more information about the updateLineage
mutation, please refer to updateLineage.
If you see the following response, the operation was successful:
{
"data": {
"updateLineage": true
},
"extensions": {}
}
curl --location --request POST 'http://localhost:8080/api/graphql' \
--header 'Authorization: Bearer <my-access-token>' \
--header 'Content-Type: application/json' --data-raw '{ "query": "mutation updateLineage { updateLineage( input:{ edgesToAdd : { downstreamUrn: \"urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)\", upstreamUrn : \"urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD)\"}, edgesToRemove :{downstreamUrn: \"urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)\",upstreamUrn : \"urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)\" } })}", "variables":{}}'
Expected Response:
{ "data": { "updateLineage": true }, "extensions": {} }
{{ inline /metadata-ingestion/examples/library/lineage_emitter_rest.py show_path_as_comment }}
Expected Outcome
You can now see the lineage between fct_users_deleted
and logging_events
.
Add Column-level Lineage
{{ inline /metadata-ingestion/examples/library/lineage_emitter_dataset_finegrained_sample.py show_path_as_comment }}
Expected Outcome
You can now see the column-level lineage between datasets. Note that you have to enable Show Columns
to be able to see the column-level lineage.
Add Lineage to Non-Dataset Entities
You can also add lineage to non-dataset entities, such as DataJobs, Charts, and Dashboards. Please refer to the following examples.
Connection | Examples | A.K.A |
---|---|---|
DataJob to DataFlow | - lineage_job_dataflow.py | |
DataJob to Dataset | - lineage_dataset_job_dataset.py |
Pipeline Lineage |
Chart to Dashboard | - lineage_chart_dashboard.py | |
Chart to Dataset | - lineage_dataset_chart.py |
Read Lineage (Lineage Impact Analysis)
query scrollAcrossLineage {
scrollAcrossLineage(
input: {
query: "*"
urn: "urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD)"
count: 10
direction: DOWNSTREAM
orFilters: [
{
and: [
{
condition: EQUAL
negated: false
field: "degree"
values: ["1", "2", "3+"]
}
]
}
]
}
) {
searchResults {
degree
entity {
urn
type
}
}
}
}
:::info Degree
Note that degree
means the number of hops in the lineage. For example, degree: 1
means the immediate downstream entities, degree: 2
means the entities that are two hops away, and so on.
:::
The GraphQL example shows using lineage degrees as a filter, but additional search filters can be included here as well.
This will perform a multi-hop lineage search on the urn specified. For more information about the scrollAcrossLineage
mutation, please refer to scrollAcrossLineage.
curl --location --request POST 'http://localhost:8080/api/graphql' \
--header 'Authorization: Bearer <my-access-token>' \
--header 'Content-Type: application/json' --data-raw '{ { "query": "query scrollAcrossLineage { scrollAcrossLineage( input: { query: \"*\" urn: \"urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD)\" count: 10 direction: DOWNSTREAM orFilters: [ { and: [ { condition: EQUAL negated: false field: \"degree\" values: [\"1\", \"2\", \"3+\"] } ] } ] } ) { searchResults { degree entity { urn type } } }}"
}}'
{{ inline /metadata-ingestion/examples/library/read_lineage_execute_graphql.py show_path_as_comment }}
The Python SDK example shows how to read lineage of a dataset. Please note that the aspect_type
parameter can vary depending on the entity type.
Below is a few examples of aspect_type
for different entities.
Entity | Aspect_type | Reference |
---|---|---|
Dataset | UpstreamLineageClass |
Link |
Datajob | DataJobInputOutputClass |
Link |
Dashboard | DashboardInfoClass |
Link |
DataFlow | DataFlowInfoClass |
Link |
Learn more about lineages of different entities in the Add Lineage to Non-Dataset Entities Section.
Expected Outcome
As an outcome, you should see the downstream entities of logging_events
.
{
"data": {
"scrollAcrossLineage": {
"searchResults": [
{
"degree": 1,
"entity": {
"urn": "urn:li:dataJob:(urn:li:dataFlow:(airflow,dag_abc,PROD),task_123)",
"type": "DATA_JOB"
}
},
...
{
"degree": 2,
"entity": {
"urn": "urn:li:mlPrimaryKey:(user_analytics,user_name)",
"type": "MLPRIMARY_KEY"
}
}
]
}
},
"extensions": {}
}
Read Column-level Lineage
You can also read column-level lineage via Python SDK.
{{ inline /metadata-ingestion/examples/library/read_lineage_dataset_rest.py show_path_as_comment }}
Expected Outcome
As a response, you will get the full lineage information like this.
{
"UpstreamLineageClass": {
"upstreams": [
{
"UpstreamClass": {
"auditStamp": {
"AuditStampClass": {
"time": 0,
"actor": "urn:li:corpuser:unknown",
"impersonator": null,
"message": null
}
},
"created": null,
"dataset": "urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD)",
"type": "TRANSFORMED",
"properties": null,
"query": null
}
}
],
"fineGrainedLineages": [
{
"FineGrainedLineageClass": {
"upstreamType": "FIELD_SET",
"upstreams": [
"urn:li:schemaField:(urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_deleted,PROD),browser_id)",
"urn:li:schemaField:(urn:li:dataset:(urn:li:dataPlatform:hive,fct_users_created,PROD),user_id)"
],
"downstreamType": "FIELD",
"downstreams": [
"urn:li:schemaField:(urn:li:dataset:(urn:li:dataPlatform:hive,logging_events,PROD),browser)"
],
"transformOperation": null,
"confidenceScore": 1.0,
"query": null
}
}
]
}
}