Enable Lineage

Alation Cloud Service Applies to Alation Cloud Service instances of Alation

Customer Managed Applies to customer-managed instances of Alation

Lineage is data about the origin of data and its movement through an organization’s data ecosystem. Lineage data documents how target data objects are created from source data objects.

To know more about lineage, see see Lineage.

The Snowflake data source supports table-level and column-level lineage. Table-level lineage is available by default. Column-level lineage is an additional paid feature that requires the Snowflake column-level lineage parser add-on. Contact Alation about purchasing this add-on.

Enable Column-Level Lineage

To enable column-level lineage:

  1. Go to Settings > Feature Configuration.

  2. Activate the toggle Automatically extracts Column Level Lineage for Snowflake data sources.

  3. Click the Save changes button to save the changes.

    ../../../_images/DS_Snowflake08.png

  4. In the Verify Feature Configuration Change dialog, click the Save Configuration button.

    ../../../_images/DS_Snowflake09.png

View Column-Level Lineage

When you enable the column-level lineage add-on, Alation will automatically generate column-level lineage data based on the existing metadata that was previously extracted with MDE, QLI, or ingested from Compose.

Note

Once the feature flag is enabled, the column-level lineage will be automatically generated only for the view definitions that are complete and already added to table-level lineage.

Complete view definition:

CREATE VIEW adbc_database_01.query_execution_main.table_view AS
  SELECT src.*
    FROM (SELECT col1, col2, col3 FROM tpch.sf1.customer LIMIT 10) src;

Incomplete view definition:

SELECT src.* FROM
  (SELECT col1, col2, col3 FROM tpch.sf1.customer LIMIT 10) src;

More column-level lineage data will be created after you perform metadata extraction (MDE), query log ingestion (QLI), and (or) use Compose to run queries that create or update column objects.

To view column-level lineage data:

  1. Go to the Lineage tab on the catalog page of a table object that should have column-level lineage.

    ../../../_images/DS_Snowflake10.png

  2. Expand the table or view lineage node to see the columns of the table or view and links to the dataflow object.

    ../../../_images/DS_Snowflake11.png

When you expand a table or view lineage node and click one of the child columns, the column-level lineage link for that particular column becomes highlighted.

../../../_images/DS_Snowflake12.png

Note

If the column-level lineage feature flag is disabled, the column-level lineage links that were generated previously are not removed. Only the future queries and query history will not be processed.