## Snowflake connector

URL: https://docs.atlan.com/apps/connectors/data-warehouses/snowflake/concepts/how-snowflake-metadata-extraction-works

> How Atlan extracts metadata from Snowflake: the two extraction strategies, where extraction runs, and how lineage and tags flow between the two

When you connect Snowflake to Atlan, two independent decisions shape every crawl: where Atlan reads metadata from (the extraction strategy) and where the extraction runs (the execution mode). This page explains the trade-offs behind each choice and how lineage and governance data flow between Snowflake and Atlan once you connect the two.

## Extraction strategy: Account usage or Information schema

Atlan can read Snowflake metadata from two sources:

- **Account Usage**: Queries the views in the `SNOWFLAKE.ACCOUNT_USAGE` schema. A single connection covers your entire Snowflake account and the grant setup is simpler. Account Usage views populate with a delay of 45 minutes to 3 hours, and the method has functional gaps: it doesn't capture external table location data or primary and foreign keys, and for Iceberg tables it reads only the table type.
- **Information Schema**: Queries the `INFORMATION_SCHEMA` views of each database you crawl. This is the more comprehensive method with no data latency, and the only method that reads the full set of Iceberg table properties, but it requires grants on every database you include, and stored procedures appear only when you grant `USAGE` on them.

The crawler's _Extraction method_ setting selects between the two. The [Permissions](https://docs.atlan.com/llms/connectors/snowflake/permissions/llms.txt) reference lists the exact grants each method needs.

## Execution mode: Direct or Agent

Independent of the extraction strategy, you choose where the extraction runs:

- **Direct**: Atlan connects to your Snowflake account and crawls metadata directly.
- **Agent**: Self-Deployed Runtime executes the extraction inside your organization's environment, for on-premises or network-restricted setups.

Any extraction strategy can run in either execution mode. The setup flow uses the phrase _extraction method_ for both choices: at the credentials step it means Direct or Agent, and on the crawler configuration it means Account Usage or Information Schema.

## Lineage from query history

Atlan builds column-level lineage for Snowflake automatically from query history. Instead of relying on manual mapping or ETL tool integrations, the lineage miner reads `QUERY_HISTORY` and `ACCESS_HISTORY` from your account's usage views and derives lineage edges from the queries your users and pipelines actually ran. Subsequent mining runs keep lineage current as your transformations change. See [Mine Snowflake](https://docs.atlan.com/llms/connectors/snowflake/mine-snowflake/llms.txt) to configure mining.

## Horizon tags

Beyond metadata extraction, Atlan reads Snowflake Horizon object tags and synchronizes them bidirectionally: tags imported from Snowflake appear on your Atlan assets, and tag values updated in Atlan can be pushed back to Snowflake. The [crawl reference](https://docs.atlan.com/llms/connectors/snowflake/what-does-atlan-crawl-from-snowflake/llms.txt) lists every object Atlan extracts and the tag fields involved.

## See also

- [Permissions](https://docs.atlan.com/llms/connectors/snowflake/permissions/llms.txt): Run the SQL grants for your chosen extraction method.
- [Crawl Snowflake](https://docs.atlan.com/llms/connectors/snowflake/crawl-snowflake/llms.txt): Configure and run the crawler to extract metadata.
- [What does Atlan crawl from Snowflake](https://docs.atlan.com/llms/connectors/snowflake/what-does-atlan-crawl-from-snowflake/llms.txt): Every object Atlan extracts, plus Horizon tag synchronization details.
- [Mine Snowflake](https://docs.atlan.com/llms/connectors/snowflake/mine-snowflake/llms.txt): Configure query-history mining for column-level lineage.
- [Choose how Atlan connects to Snowflake](https://docs.atlan.com/llms/connectors/snowflake/choose-how-atlan-connects-to-snowflake/llms.txt): Compare the network paths between Atlan and Snowflake.

_Last updated: 13 November 2026._

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