# 7.19. Redshift Connector

The Redshift connector allows querying and creating tables in an external Amazon Redshift cluster. This can be used to join data between different systems like Redshift and Hive, or between two different Redshift clusters.

## Configuration

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

connector.name=redshift
connection-url=jdbc:postgresql://example.net:5439/database
connection-user=root


### Multiple Redshift Databases or Clusters

The Redshift connector can only access a single database within a Redshift cluster. Thus, if you have multiple Redshift databases, or want to connect to multiple Redshift clusters, you must configure multiple instances of the Redshift 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 will create a catalog named sales using the configured connector.

## Querying Redshift

The Redshift connector provides a schema for every Redshift schema. You can see the available Redshift schemas by running SHOW SCHEMAS:

SHOW SCHEMAS FROM redshift;


If you have a Redshift schema named web, you can view the tables in this schema by running SHOW TABLES:

SHOW TABLES FROM redshift.web;


You can see a list of the columns in the clicks table in the web database using either of the following:

DESCRIBE redshift.web.clicks;
SHOW COLUMNS FROM redshift.web.clicks;


Finally, you can access the clicks table in the web schema:

SELECT * FROM redshift.web.clicks;


If you used a different name for your catalog properties file, use that catalog name instead of redshift in the above examples.

## Redshift Connector Limitations

The following SQL statements are not yet supported: