Presto 330 Documentation

6.23. Snowflake Connector

6.23. Snowflake Connector

The Snowflake connector allows querying and creating tables in an external Snowflake account. This can be used to join data between different systems like Snowflake and Hive, or between two different Snowflake accounts.

Configuration

To configure the Snowflake connector, create a catalog properties file in etc/catalog named, for example, snowflake.properties, to mount the Redshift connector as the snowflake catalog. Create the file with the following contents, replacing the connection properties as appropriate for your setup:

connector.name=snowflake
connection-url=jdbc:snowflake://<account>.snowflakecomputing.com>/?db=<database>
connection-user=root
connection-password=secret
scan-cache-enabled=true

Transparent scan cache

Transparent scan cache can be enabled to cache data scans from Snowflake to in memory Ampool connector. On subsequent access, Snowflake data scan will be replaced by cached Ampool table scan, improving performance. Cache invalidation mechanism deletes cached tables based on data change and Ampool resource consumption. Transparent scan cache can be enabled by setting ‘scan-cache-enabled=true’ in Snowflake catalog properties file. Also, there is session property ‘query_scancaching_enabled’ to enable/disable transparent scan cache for a particular session. Note that both, properties file cache property and session cache property must be ‘true’ to use transparent cache.

Multiple Snowflake Databases or Accounts

The Snowflake connector can only access a single database within a Snowflake account. Thus, if you have multiple Snowflake databases, or want to connect to multiple Snowflake accounts, you must configure multiple instances of the Snowflake connector.

To add another catalog, simply add another properties file to etc/catalog with a different name, making sure it ends in .properties. For example, if you name the property file sales.properties, Presto creates a catalog named sales using the configured connector.