Thank you for posting your question on Microsoft Q&A and for using Azure services.
My understanding is that you are asking if there are hidden cost when creating an Azure MYSQL DB. Please let me know if my understanding is not correct.
The answer is there is no hidden costs. Compute and storage are the only costs.
According to this documentation [https://learn.microsoft.com/en-us/azure/mysql/flexible-server/concepts-service-tiers-storage#pricing For the most up-to-date pricing information, see the service pricing page. To see the cost for the configuration you want, the Azure portal shows the monthly cost on the Compute + storage tab based on the options you select. If you don't have an Azure subscription, you can use the Azure pricing calculator to get an estimated price. On the Azure pricing calculator website, select Add items, expand the Databases category, choose Azure Database for MySQL, and Flexible Server as the deployment type to customize the options.
Hope this helps.
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