This topic provides answers to some frequently asked questions about the pricing and the purchase of PolarDB.

FAQ about compute nodes and storage

  • What is the price if I add a read-only node?

    The price of a read-only node is the same as that of the primary node of your cluster. For more information, see Pricing of compute nodes.

  • Is the storage capacity doubled after I add a read-only node?

    No, the storage capacity is not doubled after you add a read-only node. PolarDB uses an architecture where computing is decoupled from storage. The read-only nodes that you purchase are computing resources. Therefore, the storage capacity is not increased.

    A serverless architecture is used for storage. Therefore, you do not need to select the capacity when you purchase clusters. The capacity is automatically increased when the amount of data increases. You are charged for only the used storage. Each cluster specification has the corresponding maximum storage capacity. To increase the maximum storage capacity, upgrade your cluster specifications. For more information, see Upgrade cluster specifications.

FAQ about storage plans

  • Are storage plans bound to clusters for sale?

    No, storage plans are not bound to clusters for sale. You must purchase storage plans in a separate way. The storage that is used by the clusters in the related regions is automatically deducted from the storage plans. For more information, see Together with storage plans.

  • Can a storage plan be shared by multiple clusters?

    Yes, a storage plan can be shared by multiple clusters. A storage plan can be used by all the clusters in the regions that are specified by the Plan Type parameter. You can specify Mainland China or China (Hong Kong) and regions outside China as the value of the parameter. For more information, see Purchase a storage plan.

  • Can a storage plan be shared by the clusters that use different engines?

    Yes, a storage plan can be shared by PolarDB for MySQL, PolarDB for PostgreSQL, and PolarDB-O clusters.

  • What can I do if the storage capacity of my storage plan is insufficient or has been exhausted? Can I purchase another storage plan of the same type?

    No, you cannot purchase another storage plan of the same type. You can purchase only one storage plan of each type. If the storage capacity of your storage plan is insufficient or has been exhausted, you can upgrade the storage plan. For more information, see Renew or upgrade a storage plan.

  • How am I charged for the storage that exceeds the storage capacity of my storage plan?

    You are charged for the storage that exceeds the storage capacity of your storage plan based on the pay-as-you-go method. For more information, see Storage pricing.

  • The storage capacity of a storage plan can be 3 TB or 5 TB. If my services require 4 TB storage, which storage plan do I purchase?

    We recommend that you purchase a 3 TB storage plan. If the amount of your stored data increases to about 5 TB later, we recommend that you upgrade the storage plan to a 5 TB storage plan. For more information, see Upgrade a storage plan.

  • How can I renew my storage plan if the storage plan is about to expire?

    You can renew your storage plan in the user center. For more information, see Renew a storage plan.

  • Are storage plans used to deduct only the storage fees of PolarDB clusters?

    No, storage plans can also be used to deduct the fees of the used excess storage for level-1 backups in PolarDB clusters. For level-1 backups, you are charged for only the storage that exceeds the free quota. For more information, see Billing methods of data backup.

  • Are storage fees deducted from storage plans based on priorities? Can I use storage plans to deduct the storage fees of clusters first before I use the storage plans to deduct other storage fees?

    Storage plans are first used to deduct the fees of the used storage of PolarDB clusters. Then, the remaining quota of the storage plans is used to deduct the fees of the used excess storage for level-1 backups. For level-1 backups, you are charged for only the storage that exceeds the free quota.

  • What is the deduction ratio when I use a storage plan to deduct the fees of the used storage for level-1 backups?

    The deduction ratio is 1:1. This means that a 1 GB storage plan can be used to deduct the fees of 1 GB storage for level-1 backups.

  • What can I do if the used storage for level-1 backups exceeds the free quota and the remaining quota of my storage plan cannot cover the excess storage?

    If the remaining quota of your storage plan cannot cover the excess storage for level-1 backups, you are charged for the excess storage based on the pay-as-you-go method. You can also upgrade the storage plan to increase the storage capacity. For more information, see Upgrade a storage plan.