Update Considerations

This article provides guidelines on how to prepare before updating your Exasol database.

Updating Exasol to a new version normally requires only minimal system downtime and will not put your data at risk, provided that you plan carefully and observe some basic considerations such as creating a backup. We recommend that you test the new version in a separate environment before you update the production system.

The following guidelines will help you to ensure a successful update. If you need further help, create a support case.

Planning

Planning is crucial for keeping the maintenance window to a minimum and to ensure a successful update.

  • Read the relevant release notes (change logs) to understand the changes in the new version, how they may affect your system, and to determine how critical the update is for your operations.

    The release notes describe the changes that are introduced with each new version within the Exasol release cycle. For example, the change log for Exasol 7.1.21 describes the changes between Exasol 7.1.20 and Exasol 7.1.21. To see all changes between your current version and the version you are updating to, you must read the change logs for all the interim releases.

    For more information about different Exasol release types, see Product Life Cycle.

  • Plan the update for a time when it will have minimum impact on your business operations.

    For example, do not plan to update your system close to or during a business-critical event such as a product release, since an update will always involve some downtime.

  • Include a full backup of your data and of BucketFS in your update plan.

    Creating a backup before the update is optional but recommended in all scenarios, since it will allow you to roll back the update without losing data. A backup is always required in the following scenarios:

    • When an update of the operating system is included in the new Exasol version. The update will then consist of a fresh installation followed by restoring data from a backup of your old Exasol version.

    • When migrating from Exasol 7.1 to Exasol 8 or later. For more information, see Migrate from Exasol 7.1 to Exasol 8.

    To learn more about backups, see Backup and Restore. To learn how to manage files in BucketFS, see BucketFS Client.

Testing

To ensure that the production system will perform as expected after the update, we recommend that you first install it in a test environment that mimics your production system. The testing should ideally cover all your relevant business use cases. The following steps can be used as a starting point:

  1. Define acceptance criteria for the new Exasol version. Include any integrations and script languages that should be supported.

  2. Install the new Exasol version on a test system that resembles your production system as much as possible and has the same basic structure of users, roles, schemas, tables, etc.

  3. Run acceptance tests on the test system.

    • Base the tests on the changes that were introduced between your current version and the new version.

    • Try to mimic the typical load on your production system in the tests.

    • Test the most frequently used queries from your production system. You can deduce this from the audit logs.

    • Test all UDFs that you are currently using in your production system.

    • If the new Exasol version supports a new version of a driver or tool, use the latest supported version in your tests.