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We are currently doing a POC on migrating on-premises SQL DBs to Azure SQL Database. While migrating , we hit with an issue on applying schemas - few of the Stored procedure calls other DBs.

Scenario is like we have central DB- A, and there is another application DB - B. Application DB has some stored procedures which has reference to central DB - A(basically select and joins).

When we searched MS site, found an article on create external table Link as a fix for the issue. If you have multiple DBs' with multiple references, things gets complicated.

So I am thinking of using Azure SQL Managed Instance , so just before spinning up one and wanted to get an suggestion, whether the same case would be there in the managed instance as well?

Renji
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You can do cross-db queries in SQL MI just like you do in SQL Server on-premises. There is a substantial perf difference in using external tables, so I don't recommend you go that route for migrating an existing multi-db app unless you have only modest background perf requirements for queries that go cross-database. External tables is very much like linked servers in terms of performance (with the caveat that there are different kinds of external tables and there is some variance in how each type is implemneted - they are all slower than normal intra-instance cross-db query in SQL Server)

Conor Cunningham MSFT
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