A search for sql in the Azure portal provides multiple results. I have marked some of them to show the resources that can be used directly for OLTP applications:
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The previous screenshot shows the varied features and options available for creating SQL Server-based databases on Azure.
Again, a quick search for database on the Azure portal provides multiple resources, and the marked ones can be used for OLTP applications:
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The previous screenshot shows resources provided by Azure that can host data in a variety of databases, including the following:
- MySQL databases
- MariaDB databases
- PostgreSQL databases
- Cosmos DB