PolarDB:Billing method 1: pay-as-you-go + storage plans (recommended)

Storage plans can be used by all PolarDB clusters in the regions that are specified by the Plan Type parameter. You can select Chinese Mainland or Outside Chinese Mainland for this parameter.

If the capacity of your storage plan is insufficient, you can purchase an additional storage plan or upgrade the storage plan. However, you cannot downgrade storage plans that you purchase. For more information about how to upgrade a storage plan, see Upgrade a storage plan.

If the amount of the storage that is used exceeds the capacity of your storage plan, you are charged for the additional storage resources based on the pay-as-you-go billing method.

For example, you have created three PolarDB clusters that each have 400 GB of storage. If you purchase a storage plan of 1,000 GB and these clusters share the storage plan, the storage resources used in excess of 200 GB are billed on a pay-as-you-go basis. For more information, see View the database storage usage.

The pay-as-you-go + storage plans billing method combines the cost-effectiveness of the subscription billing method and the flexibility of the pay-as-you-go billing method.

• The pay-as-you-go billing method uses a serverless approach. You do not need to specify the storage capacity when you purchase clusters. The storage capacity is automatically increased when the amount of data increases. You are charged only for the storage that you use.

• In most cases, the pay-as-you-go + storage plans billing method costs less than the pay-as-you-go billing method. The discount rate that a storage plan provides varies based on the storage capacity and validity period of the storage plan. In some cases, the discount rate can reach 45% compared with the pay-as-you-go billing method.

This billing method has extensive coverage. Storage plans take effect for all clusters in a specific region within your Alibaba Cloud account instead of only for a single cluster.

• A Chinese Mainland storage plan can be used to offset the storage fees of all clusters in all regions in the Chinese mainland within your Alibaba Cloud account.

• An Outside Chinese Mainland storage plan can be used to offset the storage fees of all clusters in the following regions within your Alibaba Cloud account: China (Hong Kong), Singapore (Singapore), Malaysia (Kuala Lumpur), Indonesia (Jakarta), India (Mumbai), US (Silicon Valley), US (Virginia), Japan (Tokyo), Germany (Frankfurt), UK (London), and Australia (Sydney).

When your storage plans are exhausted, data can still be written to your clusters as expected. You are charged for the excess storage usage on a pay-as-you-go basis.

Your Alibaba Cloud account has clusters that store a large amount of data in specific regions. If you want to store a large amount of data, such as 1,000 GB of data or more, storage plans are more cost-effective than the pay-as-you-go billing method. Higher discounts are offered for storage plans that have larger storage capacities. For more information, see Purchase a storage plan.

The amount of data generated by your business is prone to frequent fluctuations.

You have multiple pay-as-you-go clusters.

For information about how to use the pay-as-you-go storage billing method for a cluster, see Purchase a pay-as-you-go cluster and Purchase a subscription cluster.

For information about the discount rates of storage plans and how to purchase storage plans, see Purchase a storage plan.