Azure SQL Database: local to cloud, same code

Build and test against the local Azure SQL Developer, then deploy the same application code to Azure SQL Database in the cloud. Only the connection string changes. Nothing else.

This works because the local container is the Azure SQL Database engine, not the SQL Server image. SELECT SERVERPROPERTY('EngineEdition') returns 5 and SERVERPROPERTY('Edition') returns 'SQL Azure', the same as the cloud. So the SQL surface your code depends on is the same in both places.

The one rule

Do not change application code between local and cloud. The application reads its connection string from a single environment variable, SQL_CONNECTION_STRING. Local development sets it to the container; cloud deployment sets it to the Azure SQL server. Same binaries, same queries, same schema.