EntityFramework 核心：当集合被继承 class 时，清除集合不会正确反映在数据库中

Question

I have 2 classes:

public class Transaction : AggregateRoot<Guid>
{
    private readonly IList<Correction> _corrections = new List<Correction>();

    public IEnumerable<Correction> Corrections => _corrections;
    public void ClearCorrections()
    {
        _corrections.Clear();
    }
}

public class Correction : Transaction
{
   ....
}

My context is as followed:

    modelBuilder.Entity<Transaction>().HasMany(p => p.Corrections).WithOne().HasForeignKey("ParentTransactionId").OnDelete(DeleteBehavior.NoAction).IsRequired();

When I clear my collection of corrections and db.SaveChanges, database is updated putting ParentTransactionId to null. Instead I would like to delete them from database.

I tried composite key on Correction but EFcore doesn't want as i cannot specify composite Key on a child.

For now, what I do is:

public async Task DeleteCorrectionsAsync(Transaction transaction, CancellationToken cancellationToken)
{
    ....
    foreach (var correction in transaction.Corrections) await Repository.RemoveAsync(correction, cancellationToken);
    
    transaction.ClearCorrections(); 
}

Is there any way i can remove the await Repository.RemoveAsync(correction, cancellationToken); ? I am sure it has been asked 1000 times, but can't find the answer... Thanks !

Answer 1

Clearing a Navigation Property collection does not delete the elements. You could however do

_corrections.ToList().ForEach(e => _corrections.Remove(e))

and then save changes

Answer 2

Clear() won't affect your database, for this you need to use RemoveRange() from your DbSet. You can find more here .