Feature Support
Connector support for specific features is shown in the following table. Key: Y - Supported; N - Not Supported; N/A - not applicableAmazon Redshift returns whole numbers for aggregates on columns of type DECIMAL and NUMERIC types which have a 0 scale (in other words, 0 decimal places).
Connect to Amazon Redshift
Verify the MTU Size of Self-Service Analytics
Before you can establish a connection between Amazon Redshift and Self-Service Analytics, you must verify that the size of the maximum transmission unit (MTU) on your Self-Service Analytics server is set to 1500. The MTU size determines the maximum size, in bytes, of a packet that can be transferred in one Ethernet frame over your network connection. If your MTU size is too large for the connection, you might experience incomplete query results, your query might hang, or the connection might be dropped altogether. For more information, see: https://docs.aws.amazon.com/redshift/latest/mgmt/connecting-drop-issues.html. To review the MTU value, use theip command:
ip command:
Configure and Reference the JDBC Driver
The Amazon Redshift connector requires a JDBC driver to be configured before you connect. You can download the driver from the vendor’s site. If you are upgrading, keep in mind you need to configure the JDBC driver- see Upgrade Self-Service Analytics. For more information, see Add a JDBC Driver. The JDBC Driver for Redshift has more than one jar file that needs to be downloaded: be sure to place the files in the same location to avoid any issues. When setting up your Amazon Redshift connection, you need to specify the JDBC URL. You can find the URL on the Configuration tab of a cluster under Cluster Database Properties. The format varies slightly based on the type of database being connected. For Amazon Redshift, use the following format:jdbc:redshift://HOSTNAME:PORT/DATABASE_NAME . If authentication has been set up, provide the user name and password.
Troubleshoot the Amazon Redshift Connector
The Self-Service Analytics Amazon Redshift connector lets you access the data available in Amazon Redshift storage using the Self-Service Analytics client. You can troubleshoot out of memory errors that may occur when executing heavy queries against large databases.Out Of Memory Errors
To troubleshoot out of memory errors, you will need to set the connector log to DEBUG mode. Edit the Redshift configuration file,edc-redshift.properties. See Connector Properties and Property Files. Use the information available in the log to adjust your environment to prevent further errors.
After you set your log to DEBUG mode, run your queries again. Review the logs, and use one or more approaches to resolve the out of memory issues.
- Rewrite your most memory-consuming queries to return more granular results.
- Increase the RAM allocation in your Self-Service Analytics environment for this connector. See Configure Memory Settings.
- Increase the
wlm_query_slotcount in your AWS environment. See Troubleshooting queries - Amazon Redshift.