This is expected as there is no provision in Azure SQL Database to keep the database in an offline state to save on billing.
However, to save money, you can opt for the serverless pricing tier. The serverless compute tier automatically pauses databases during inactive periods, during which only storage is billed. It also automatically resumes databases when activity returns.
Please note, Auto-pausing and auto-resuming is currently only supported in the General Purpose service tier.
Here is reference document - https://learn.microsoft.com/en-us/azure/azure-sql/database/serverless-tier-overview?view=azuresql&tabs=general-purpose
Let us know if you have any questions or need additional information.
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