C＃实体框架迁移，使ID自动递增

Question

I have a table that is used in an Entity Framework context that was generated using a database-first approach.

I made a mistake, and the ID for one table is not auto-incrementing. I am unsure as to what the best approach to solve this is.

Should I drop the table, and generate it again?

Can I make a migration to make this ID auto-increment?

Is there another option?

Thanks in advance

Answer 1

If the table was created using Database first you can alter it in SSMS if you use this? Then open up the .edmx file in Visual Studio, right click the background somewhere and select update model from database. Go through the options you need (probably just the refresh table), once you have done this you will need to save the .edmx file.

Answer 2

You can enable code first migrations and update your database:

1. Add [DatabaseGenerated(DatabaseGeneratedOption.Identity)] attribute to your ID column

2. Run this command in Package Manager Console to enable migrations:

    Enable-Migrations 

3. Update database using these commands :

    Add-Migration Update-Database 

   (First run Add-Migration , and then run Update-Database command)