Load data from Amazon Redshift

This section describes how to connect to Amazon Redshift with Exasol and then load data.

To view details about data type mappings or to migrate data, see the Amazon Redshift to Exasol migration script in our GitHub repository.

Prerequisites

  • Amazon Redshift must be reachable from the Exasol system.

  • The user credentials in the connection must be valid.

Download driver

Download the compatible JDBC 4.2 driver from AWS Documentation.

Configure driver in EXAoperation

Do the following to configure the driver in EXAoperation:

  1. Log in to EXAoperation user interface as an Administrator user.
  2. Select Configuration > Software and click the JDBC Drivers tab.
  3. Click Add to add the JDBC driver details.
  4. Enter the following details for the JDBC properties:
    • Driver Name: Redshift
    • Main Class: com.amazon.redshift.jdbc42.Driver
    • Prefix: jdbc:redshift:
    • Disable Security Manager: Check the box to disable the security manager. This allows the JDBC Driver to access certificate and additional information.
    • Comment: This is an optional field.
  5. Click Add to save the settings.
  6. Select the radio button next to the driver from list of JDBC driver.
  7. Click Choose File to locate the downloaded driver and click Upload to upload the JDBC driver.

Create connection

To create a connection, run the following statement. Replace the connection string and credentials with the corresponding values for your account. 

CREATE OR REPLACE CONNECTION jdbc_connection_1
TO 'jdbc:redshift://example_cluster123.some_region.redshift.amazonaws.com:5439/dev' 
USER 'awsuser' 
IDENTIFIED BY'some_password';

To check the connection, run the following statement.

import from jdbc at jdbc_connection_1 statement 'select 42';

Load data

You can use the IMPORT statement to load data using the connection you created above. IMPORT supports loading data from a table or a SQL statement.

Troubleshooting error messages

Error message 1

[ETL-5] JDBC-Client-Error: Connecting to 'jdbc:redshift://example_cluster123.some_region.redshift.amazonaws.com:5439/dev' as user='awsuser' failed: [Amazon](500150) Error setting/closing connection: Error loading the keystore . (Session: 1622834984232180908)

Solution

Ensure that you have selected the Disable Security Manager in EXAoperation as mentioned in Configure driver in EXAoperation.

Error message 2

[ETL-5] JDBC-Client-Error: Connecting to 'jdbc:redshift://example_cluster123.some_region.redshift.amazonaws.com:5439/dev' as user='awsuser' failed: [Amazon](500150) Error setting/closing connection: Connection timed out. (Session: 1622834984232180908)

Solution

Check that the security groups on the Redshift side allow your VM/cluster to connect to Redshift.

Error message 3

[ETL-5] JDBC-Client-Error: Connecting to 'jdbc:redshift://example_cluster123.some_region.redshift.amazonaws.com:5439/dev' as user='awsuser' failed: [Amazon](500150) Error setting/closing connection: UnknownHostException. (Session: 1622834984232180908)

Solution

Ensure that a DNS server is configured in EXAoperation.

Error message 4

[ETL-5] JDBC-Client-Error: Connecting to 'jdbc:redshift://example_cluster123.some_region.redshift.amazonaws.com:5439/dev' as user='awsuser' failed: SSL error: PKIX path validation failed: java.security.cert.CertPathValidatorException: validity check failed

Solution

Add ;ssl=false to the connection string. For example:

jdbc:redshift://example_cluster123.some_region.redshift.amazonaws.com:5439/dev;ssl=false