Scaling SaaS model (one DbContext, database-per-tenant) with EF Core?

There doesn't seem to be any good guidance on how to set up and maintain a database-per-tenant model for EF Core.

- How to create/ migrate new tenant dbs programmatically?
- How to manage connection strings?
- How to select a specific tenant at runtime?

Sharding seemed to be supported in .NET 4.x but no support in .NET Core or beyond. How is EF Core used in a scalable, sustainable manner in a SaaS environment with tenant data isolation?

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#### Document Details

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* ID: bb29a2b6-c401-287f-2da9-1aeb3c633b41
* Version Independent ID: bb29a2b6-c401-287f-2da9-1aeb3c633b41
* Content: [Multi-tenancy - EF Core](https://docs.microsoft.com/en-US/ef/core/miscellaneous/multitenancy)
* Content Source: [entity-framework/core/miscellaneous/multitenancy.md](https://github.com/dotnet/EntityFramework.Docs/blob/main/entity-framework/core/miscellaneous/multitenancy.md)
* Product: **entity-framework**
* Technology: **entity-framework-core**
* GitHub Login: @JeremyLikness
* Microsoft Alias: **jeliknes**