When you change the specifications of a PolarDB for PostgreSQL cluster, fees are recalculated based on your billing method. This topic explains how upgrade fees and downgrade refunds are calculated for each billing type.
Pay-as-you-go
Pay-as-you-go clusters are billed hourly. After a configuration change takes effect, the cluster is charged at the new hourly rate.
Subscription
Upgrade specifications or add nodes
You pay the difference between the new and original configurations for the remaining subscription period.
Formula:
Fees = (New monthly price / 30 / 24 × remaining hours) − (Original monthly price / 30 / 24 × remaining hours)Example:
| Item | Value |
|---|---|
| New monthly price | USD 14,400 |
| Original monthly price | USD 7,200 |
| Remaining subscription period | 50 days (1,200 hours) |
| Fees | (14,400 / 30 / 24 × 1,200) − (7,200 / 30 / 24 × 1,200) = USD 12,000 |
Downgrade specifications or delete nodes
The system refunds the difference between the original and new configurations for the remaining subscription period. The refund is calculated based on the amount you actually paid, not the list price.
Formula:
Refund = (Original monthly price / 30 / 24 × remaining hours) − (New monthly price / 30 / 24 × remaining hours)Example:
| Item | Value |
|---|---|
| Subscription period | 3 months |
| Original price | USD 3,500 |
| Amount paid (after coupons) | USD 3,000 |
| After 2 months, remaining fees at original rate | USD 1,000 |
| New configuration monthly price | USD 800 |
| Refund | USD 1,000 − USD 800 = USD 200 |
FAQ
Why is my refund less than expected?
Refunds are based on the amount you actually paid, not the list price. Two common reasons:
Discounts: If you received a discount on the original order — for example, the 15% discount for subscriptions of one year or longer on alibabacloud.com — the discounted amount is used as the basis for the refund calculation. For instance, if the list price was USD 1,000 and you paid USD 850, the refund is calculated from USD 850.
Coupons: If you used coupons and paid USD 500, the refund is calculated from USD 500.
What's next
Change specifications — PolarDB for PostgreSQL
References
- Manual configuration changes:
You can manually change the configuration of your cluster as needed. For more information, see Manually change configurations and Add or remove nodes.
- Automatic configuration changes:
PolarDB for MySQL can be used with the auto scaling service of Database Autonomy Service (DAS). You can customize the trigger conditions for auto scaling based on the peaks, valleys, and frequency of your business workloads. When the conditions are met, PolarDB for MySQL automatically scales the cluster specifications up or down step by step.