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“dotnet ef script” or “Script-Migration” producing empty .sql files?

Another day, another issue. This time, I was absent-mindedly following the guidance for a project on how to generate .sql files for .NET EF Core code-first migrations. Don’t ask why that was required, but it was. My migration was simple. Adding an entity with just a few properties. And Entity Framework created my programmatic migration just fine. But when generating the SQL file, I got nothing but an empty file.…Continue reading “dotnet ef script” or “Script-Migration” producing empty .sql files?

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The easiest way to debug Seed-method in Code-first migrations in Entity Framework

This post describes the easiest way to debug the issues that may stop your Seed-method in Configuration.cs from going through. This problem concerns typically your ASP.NET MVC projects, either on .NET Framework or .NET Core – the same basic idea should work for both situations. The solution here shows you, how you can get a little bit more information out of the process, without attaching the debugger (there’s another blog…Continue reading The easiest way to debug Seed-method in Code-first migrations in Entity Framework

Applying Entity Framework’s Code-First Migrations against a Database in Azure by running Update-Database

This post describes how to run Entity Framework’s code-first migrations against a database located in Windows Azure. This is done by running the Update-Database commandlet with suitable switches, see below. The problem and symptoms Okay, so you’re developing your MVC+EF cool web app with a database in Azure, and you’re using code-first migrations. Cool! What’s nice with code-first-migrations is the fact they are run automatically even in the cloud the…Continue reading Applying Entity Framework’s Code-First Migrations against a Database in Azure by running Update-Database

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Fixing the error: “Column XX in table dbo.YY is of a type that is invalid for use as a key column in an index.”

While using Entity Framework and code-first migrations, Entity Framework (EF) creates the indexes for you – but what if you need to create a custom one, explicitly based on a certain field/column? Then you’ll have to tell EF which one to use as a key column. Usually, it’s easy – you just add the following annotation to the columns you’ll be using: [Index(“OfficialIds”, 1)] public int AreaId { get; set; } [Index(“OfficialIds”, 2)] public string EstateId { get; set; } (example stripped of extra…Continue reading Fixing the error: “Column XX in table dbo.YY is of a type that is invalid for use as a key column in an index.”

Entity Framework's Update-Database throwing an error

Fixing “An error occurred while updating the entries” while running code-first migrations in MVC 5 app

This post describes an issue with EF’s code-first migrations, when mapping between DB’s DateTime (datetime2) and C#’s DateTime simply fails, and results in the Update-Database cmdlet failing, too. It is more or less a prime example of a situation, where the error itself tells very little about the actual issue, and since debugging code-first migrations is kind of difficult (see the best tips for that here!), it’s cumbersome to investigate.…Continue reading Fixing “An error occurred while updating the entries” while running code-first migrations in MVC 5 app