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.
Requirements#
To connect to Redshift, you need:
Network access from the Trino coordinator and workers to Redshift. Port 5439 is the default port.
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:redshift://example.net:5439/database
connection-user=root
connection-password=secret
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
, Trino creates 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.
Type mapping#
General configuration properties#
The following properties can be used to configure how data types from the connected data source are mapped to Trino data types and how the metadata is cached in Trino.
Property name |
Description |
Default value |
---|---|---|
|
Configure how unsupported column data types are handled:
The respective catalog session property is |
|
|
Allow forced mapping of comma separated lists of data types to convert to
unbounded |
|
|
Support case insensitive database and collection names |
False |
|
1 minute |
|
|
Duration for which metadata, including table and column statistics, is cached |
0 (disabled caching) |
|
Cache the fact that metadata, including table and column statistics, is not available |
False |
SQL support#
The connector provides read access and write access to data and metadata in Redshift. In addition to the globally available and read operation statements, the connector supports the following features:
SQL DELETE#
If a WHERE
clause is specified, the DELETE
operation only works if the
predicate in the clause can be fully pushed down to the data source.