c# - Entity Framework error "Column names in each table must be unique"

Question

I have manually added the column IdCategory to my table Books, and now each time I try to run Update-Database, I get this error:

fail: Microsoft.EntityFrameworkCore.Database.Command[20102]

Failed executing DbCommand (43ms) [Parameters=[], CommandType='Text', CommandTimeout='30']
ALTER TABLE [Books] ADD [IdCategory] nvarchar(max) NULL;

Failed executing DbCommand (43ms) [Parameters=[], CommandType='Text', CommandTimeout='30']

Column names in each table must be unique. Column name 'IdCategory' in table 'Books' is specified more than once.

I have found in many forums this type of problem but the solutions don't solve in my case.

How I can solve this problem ?

Here are my models:

public class Book
{
        [Key]
        public int Id { get; set; }
        [Required]
        public string Name { get; set; }
        public string Author { get; set; }
        public string ISBN { get; set; }
        public int IdCategory { get; set; }
}

public class BookCategory
{
    [Key]
    public int IdCategory  { get; set; }

    [Required]
    public string Description { get; set; }
}

Answer 1

Try running add-migration, then delete the code within it and then apply an update-migration. That should sync your model with the database.