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    PolarDB:Change configuration

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    PolarDB:Change configuration

    Last Updated:Jul 24, 2026

    When you change a cluster's configuration, the system calculates fees based on the cluster's billing method and the changes made.

    Important notes

    After you change the configuration—either manually or through auto scaling—you are billed based on the new configuration.

    Subscription

    Change type

    Fee description

    Upgrade or add nodes

    Payment fee = Total price for the remaining duration of the new configuration (monthly price of the new configuration ÷ 30 ÷ 24 × remaining subscription duration) − total price for the remaining duration of the old configuration (monthly price of the old configuration ÷ 30 ÷ 24 × remaining subscription duration).

    Example: The new configuration costs USD 14,400 per month, and the old configuration costs USD 7,200 per month. The subscription has 50 days remaining. The fee to pay is (14,400 / 30 / 24 × 50 × 24) - (7,200 / 30 / 24 × 50 × 24) = USD 12,000.

    Downgrade or delete nodes

    Refund amount = Remaining value of the original configuration (Monthly price of the original configuration / 30 / 24 × Remaining subscription duration) - Remaining cost of the new configuration (Monthly price of the new configuration / 30 / 24 × Remaining subscription duration).

    Example: The old configuration costs USD 1,000 per month, and the new configuration costs USD 800 per month. The subscription has 30 days remaining. The refund is (1,000 / 30 / 24 × 30 × 24) - (800 / 30 / 24 × 30 × 24) = USD 200.

    Note

    You can receive a refund for downgrading a subscription cluster, but you cannot receive a refund for the entire cluster. If you must do this, contact us to submit a request. If your request is approved, the subscription cluster is frozen and then automatically deleted after 14 days.

    Pay-as-you-go

    Pay-as-you-go clusters are billed hourly. After you change the configuration, they are billed hourly at the new price.

    Serverless

    You cannot manually change the configurations. The compute nodes of a Serverless cluster are dynamic resources and scale automatically based on system workload.

    Note

    You can adjust the scaling policy of cluster resources by modifying the Serverless configuration. For more information, see Set Serverless cluster resource scaling policy.

    FAQ

    Why was my refund for a downgrade less than expected?

    Check if either of the following situations occurred before the downgrade:

    • A discount was applied to the original order: For example, if you purchased the original cluster with a 15% annual discount from the official website, and the original price of the cluster was 1,000 USD, you actually paid 850 USD. The refund for the downgrade is calculated based on the actual payment of 850 USD.

    • If a voucher was applied to the original order, any refund from a downgrade is calculated based on the actual amount paid. For example, if you paid 500 USD for the original cluster after using a voucher, the refund is calculated based on this 500 USD payment.

    References

    • Manual configuration changes

      You can manually change the cluster configuration at any time as needed. For more information, see Manually change configurations and Add or remove nodes.

    • Automatic configuration changes

      PolarDB for MySQL provides multiple automatic scaling (elastic scaling) methods. You can configure relevant scaling parameters to enable elastic scaling of cluster specifications. For more information, see automatic scaling (elastic scaling).