@Cherkasov Dmitriy Welcome to Microsoft Q&A forums.
From the description of your use case, I understand that the database won't be used round the clock but in short bursts of time, when you want to your ML workloads or while updating the tables from your on-premises database.
You might want to consider Azure SQL Serverless database.
You will be billed only for the time the database is in use and it automatically pauses itself during inactive periods.
Please let us know if you have any further questions.
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