It is very frequently, that our customers ask about how to access tables from a database to another database. In Azure SQL Database there is not possible to access tables from another database in the same connection directly, for example, using database.dbo.table. We have a solution called Cross Database Queries in Azure SQL Database - https://azure.microsoft.com/es-es/blog/querying-remote-databases-in-azure-sql-db/ that you will be able to. You just only need to create an EXTERNAL DATA SOURCE and mapping the tables with another database.
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