Does EF Core ignore migrations file with old `product version`

I migrated my .NET Core 1.1 app over to .NET Core 2 and have issues with the ef db migration. I noticed that the new migration I added when my app is running .NET Core 2 seems to not have knowledge of my .NET Core 1.1 migrations. Is this because the new file has a product version of .HasAnnotation("ProductVersion", "2.0.0-rtm-26452") Where as my old ones were: .HasAnnotation("ProductVersion", "1.1.2")?

[carlos8k]

I have a same problem when migrating my project from core 1.1 to core 2.1 and I found a solution that might help other developers who encountered the same problem.

The reason for the new EF to eliminate tables that do not exist and to create tables that already exist is in the old ForSqlServerToTable method. This method (deprecated in this version, overridden by the ToTable method) has generated this code in ModelSnapshot.cs:

modelBuilder.Entity("Microsoft.AspNetCore.Identity.EntityFrameworkCore.IdentityRole", b =>
                {
                    b.Property<string>("Id")
                        .ValueGeneratedOnAdd();

                    b.Property<string>("ConcurrencyStamp")
                        .IsConcurrencyToken();

                    b.Property<string>("Name")
                        .HasMaxLength(256);

                    b.Property<string>("NormalizedName")
                        .HasMaxLength(256);

                    b.HasKey("Id");

                    b.HasIndex("NormalizedName")
                        .IsUnique()
                        .HasName("RoleNameIndex");

                    b.ToTable("AspNetRoles");

                    b.HasAnnotation("SqlServer:TableName", "Roles");
                });

The new ToTable method doesn`t create “b.HasAnnotation(“SqlServer:TableName”, “Roles”);” line and not recognizes this. In other words, the new implementation consider “AspNetRoles” as current table name and then attempts to change the AspNetRoles to Roles, for example.

For workaround this behavior, I change my ModelSnapshot class manualy, removing “b.HasAnnotation(“SqlServer:TableName”, “Roles”);” line, and change “b.ToTable(“AspNetRoles”);” to “b.ToTable(“Roles”);”.

Now my code looks like this:

modelBuilder.Entity("Microsoft.AspNetCore.Identity.EntityFrameworkCore.IdentityRole", b =>
                {
                    b.Property<string>("Id")
                        .ValueGeneratedOnAdd();

                    b.Property<string>("ConcurrencyStamp")
                        .IsConcurrencyToken();

                    b.Property<string>("Name")
                        .HasMaxLength(256);

                    b.Property<string>("NormalizedName")
                        .HasMaxLength(256);

                    b.HasKey("Id");

                    b.HasIndex("NormalizedName")
                        .IsUnique()
                        .HasName("RoleNameIndex");

                    b.ToTable("Roles");
                });

That way, I was able to perform new migrations and the generated code did not want to drop and create tables.

[ajcvickers]

@p2atran Probably the best way would be to scaffold a model from the database and compare the model created from that with the one that you have. (Probably easiest way to diff would be to add an empty migration after doing the scaffolding the model and then use the model snapshot file for the diff.)