Hi Handian Sudianto, Good Day,
SQL Server will be billed on the resources that you have provisioned on the Pool and not based on the number of databases on the pool. So whether you have 10 DB's or 15 DB's on the same pool the cost will be the same till the resource allocated to the pool remains unchanged. But pls note that the performance of each individual database within the pool may vary depending on the resource utilization and demand from other databses sharing the same pool.
Thank you.
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