Extending the user model

New properties and classes

Open User.cs and add some new props.

(Collection properties must be initialized in the constructor)

public string Gender { get; set; }
public DateTime DateOfBirth { get; set; }
public string KnownAs { get; set; }
public DateTime Created { get; set; }
public DateTime LastActive { get; set; }
public string Introduction { get; set; }
public string LookingFor { get; set; }
public string Interests { get; set; }
public string City { get; set; }
public string Country { get; set; }

public ICollection<Photo> Photos { get; set; }

public User()
    Photos = new Collection<Photo>();

Create a class Photo.cs using CTRL+. on the squiggly line and choosing Generate class ‘Photo’ in new file.

Open Photo.cs and add some properties.

public class Photo
    public int Id { get; set; }
    public string Url { get; set; }
    public string Description { get; set; }
    public DateTime DateAdded { get; set; }
    public bool IsMain { get; set; }

In DatingContext.cs add a new DbSet for Photo.


Stop dotnet run or dotnet watch run

Add a new migration.

dotnet ef migrations add ExtendedUserClass

Look at the code for the migration and we see that the onDelete for the Photos table is not what we want.

Remove the last migration

dotnet ef migrations remove
dotnet ef migrations list

Reverse migration

Just as an example let’s see how to reverse a migration that was applied to the database

# Create a migration
dotnet ef migrations add ExtendedUserClass
# Apply to the DB
dotnet ef database update
# Revert to a previous migration, reverse the changes made to the database
dotnet ef database update AddedUsers

Some kind of operations are not supported by Sqlite so the update will fail. With other database (SqlServer, MariaDB, Postgresql) this operation works.

If the database is just a development we can simply drop it and the recreate it. If this is not possible there are some workaround described in the page SQLite EF Core Database Provider Limitations.

dotnet ef database drop
dotnet ef migrations remove
dotnet ef database update

Cascade delete relationship

Open Phosot.cs and reference back the User class.

The UserId is not required to make the relationship but it is necessary in all the cases where we don’t want to eagerly load.

public User User { get; set; }
public int UserId { get; set; }

Create a migration

dotnet ef migrations add ExtendedUserClass

Now if we look at the migration code we see that the Photos table has a not nullable UserId and a cascade delete.

UserId = table.Column<int>(nullable: false)
onDelete: ReferentialAction.Cascade);

Apply the migration

dotnet ef database update

Using DB browser for SQLite check the structure of the database.