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Entity Framework cannot execute ‘Update-Database’

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I am currently working on a side-project with the code-first approach. I really like how the framework does migrations and you can use the .sql files in the migration folder etc.

But I am still wrapping my head around the model/poco classes I want to use and the data structure is still changing in this stage of development. I have moved from 1-n relations to n-n etc.

I sometimes stumbled on a situation where there were foreign key constraints which made it (almost) impossible to process a migration. I also did not found how to revert one or cancel one if you have a pending one and cannot update the database.

Because I was still starting with the project I could not bother to loose all the data and start over with a clean/empty database. I have read several blogs about how to do this, but I wanted to blog my situation. Perhaps it’s useful for someone, perhaps it’s just an online note to myself.

Here is how I did it:

  1. Delete the ‘__MigrationHistory’ table
  2. Delete all files in the ‘Migrations’ folder of your project except the ‘Configuration.cs’
  3. Delete all other tables (one by one) in the DB
  4. In the package manager console, select the correct project and ‘Add-Migration <name>’
  5. Update-Database (this will recreate all tables and use the initial data from the configuration file, if you had any)

A lot of blogposts are based on keeping your data. In that case, you should skip step 3 (obvious) and comment out the ‘Up’ method when you have added your migration and have the generated file open.

This is a slightly modified version of this blogpost which uses the brand new SQL Operations Studio 0.23.6


Good luck!


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