PolarDB allows you to use the backup and restoration features free of charge, but you are charged for the storage space occupied by backup files. This topic describes the billing rules for the storage space occupied by PolarDB backup files.
Free quota
PolarDB Standard Edition provides a free quota for backup storage space. After the backup storage space exceeds the free quota, you are charged based on the storage usage and the retention period of the backup files. Backup files include data and log backup files.
Backup type | Free quota |
Data backup | Database storage usage × 50% |
Log backup | 100 GB |
Billing rules
Region in the Chinese mainland | Hong Kong (China) and regions outside China | Billing method |
USD 0.000032 per GB-hour | USD 0.000045 per GB-hour | Backup storage fee per hour = Total size of backup files × Unit price per hour For example, a PolarDB for MySQL cluster deployed in the Chinese mainland uses 1000 GB to store backup files, the backup storage fee per hour is USD 0.000032. The data backup fee is calculated by using the following formula: 1,000 GB × USD 0.000032/GB/hour = USD 0.032/hour. |
Use storage plans to offset data backup fees
You can use storage plans to offset data backup fees. If your storage plans do not have sufficient capacity to offset the data backup storage usage, you are charged for the excess storage usage based on the pay-as-you-go billing method.
The following table describes the offset rules.
Region | Offset ratio | Data backup storage usage offset by a 1-GB storage plan |
Regions in the Chinese mainland | 0.043 | 1/0.043=23.26 GB |
Hong Kong (China) and regions outside China | 0.054 | 1/0.054=18.52 GB |
For example, if you purchase a 100-GB storage plan and 50 GB of the plan is used to offset the storage usage of the cluster, the storage plan has 50 GB of remaining capacity. If your cluster consumes an additional 50 GB of storage space for data backups in a region in the Chinese mainland, 2.15 GB (50/23.26) from the storage plan automatically offsets this storage usage. As a result, the storage plan has 47.85 GB of remaining capacity.
If the remaining capacity of the storage plan is insufficient to offset the data backup storage usage, you are charged for the excess storage usage based on the pay-as-you-go billing method.
For more information about storage plans, see FAQ about billing for storage plans.
Use storage plans to offset log backup storage fees
You can use storage plans to offset the storage usage of log backups. If the storage plans do not have sufficient capacity to offset the log backup storage usage, you are charged for the excess storage usage based on the pay-as-you-go billing method.
The following table describes the offset rules.
Region | Offset ratio | Log backup storage usage offset by a 1-GB storage plan |
Regions in the Chinese mainland | 0.043 | 1/0.043=23.26 GB |
Hong Kong (China) and regions outside China | 0.054 | 1/0.054=18.52 GB |
For example, if you purchase a 100-GB storage plan and 50 GB of the plan is used to offset the storage usage of the cluster, the storage plan has 50 GB of remaining capacity. If your cluster consumes an additional 50 GB of storage for log backups in a region in the Chinese mainland, 2.15 GB (50/23.26) from the storage plan automatically offsets this storage usage. As a result, the storage plan has 47.85 GB of remaining capacity.
If the remaining capacity of the storage plan is insufficient to offset the log backup storage usage, you are charged for the excess storage usage based on the pay-as-you-go billing method.
For more information about storage plans, see FAQ about billing for storage plans.