Data Annotations seems doesn't work in derived class

[BigVan]

Hi~
When I am using EF core to create MySQL table (using MySQL.Data.EntityFrameworkCore Package), I found some problems that Data Annotations [Column( TypeName = "varchar(200)" ] seems doesn't work.

Steps to reproduce

Here is my code:

public class BasicObject
{
        [DatabaseGenerated(DatabaseGeneratedOption.Identity)]
        public int Id { set; get; }

        public string Name { set; get; }

        [Column(TypeName = "varchar(200)")]
        public string Description { set; get; }
}

public class Item : BasicObject
{
        public int Type { set; get; }

        public double Price { set; get; }
        
        public string Image { set; get; }
}

public class DBManager : DbContext
{
    public DBManager(DbContextOptions<DBManager> options)
    : base(options)
    { }

    public DbSet<Item> Items { get; set; }
  
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Item>().ToTable("Items");       
    }
}

When the database created, the type of column 'Description' is still varchar(255).

However, when I use 'Fluent API' as follow:

modelBuilder.Entity<Item>().ToTable("Items")
                        .Property(b=>b.Description).HasColumnType("varchar(200)");

It can change the column type to varchar(200).

So, Is this a bug ?

Further technical details

Visual studio version: 2015-community update3

[rowanmiller]

What version of EF Core are you using?

[BigVan]

MySQL.Data.EntityFrameworkCore (7.0.6-IR31)

[AndriySvyryd]

@BigVan This should have been fixed in 1.0.1. Update Microsoft.EntityFrameworkCore.Relational to 1.0.1 and try again.
If it still fails try updating further to 1.1.0, though it will probably require updating other components, depending on what you are using, see https://blogs.msdn.microsoft.com/dotnet/2016/11/16/announcing-net-core-1-1/

[kdazzle]

I'm getting this too - my annotations don't seem to work for SQLite, but they're fine through the fluent api.

here are my dependencies:

"dependencies": {
    "Microsoft.EntityFrameworkCore": "1.1.0",
    "Microsoft.EntityFrameworkCore.Relational": "1.1.0",
    "Microsoft.EntityFrameworkCore.Relational.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Sqlite": "1.1.0",
    "Microsoft.EntityFrameworkCore.Sqlite.Design": "1.1.0",
    "Microsoft.EntityFrameworkCore.Tools": "1.1.0-preview4-final",
    "Microsoft.NETCore.UniversalWindowsPlatform": "5.2.2"
  },

Or am I using the wrong annotation library? I couldn't find any mention of the one to use in the documentation, but I saw System.ComponentModel.DataAnnotations being used in some of the tests.

Here is an example class:

using System;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Collections.Generic;

namespace Foo.models
{
    public class Foo
    {
        public int Id { get; set; }

        [Required, MaxLength(512)]
        public string Name { get; set; }
    }
}

[AndriySvyryd]

This is a known issue: data annotations don't work on UWP, see #5471