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Этот вопрос касается ядра EF.

Я получаю эту ошибку, когда я «dotnet ef обновляю базу данных»:

 Introducing FOREIGN KEY constraint 'FK_PupilTests_Tests_TestId' on table 'PupilTests' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints.
Could not create constraint or index. See previous errors.
 

Я понимаю, почему я получаю эту ошибку, и я попытался устранить ошибку, правильно настроив DeleteBehavior, но это просто не работает.

Так что же не так с моей свободной конфигурацией?

Свободная настройка:

 builder.Entity<Test>().HasMany<PupilTest>(x => x.PupilsTests).WithOne(p => p.Test).HasForeignKey(p => p.TestId).OnDelete(DeleteBehavior.Restrict);

builder.Entity<Pupil>().HasMany<PupilTest>(x => x.PupilsTests).WithOne(p => p.Pupil).HasForeignKey(p => p.PupilId).OnDelete(DeleteBehavior.Restrict);
 

Модель

 public class Pupil
{
    public Pupil()
    {
        PupilsTests = new HashSet<PupilTest>();

    }

    public int Id { get; set; }
    public ISet<PupilTest> PupilsTests { get; set; }
}


public class PupilTest
{
    public int PupilId { get; set; }
    public int TestId { get; set; }
    public decimal Scores { get; set; } 
    public Pupil Pupil { get; set; }
    public Test Test { get; set; }
}

public class Test
{
    public Test()
    {
        PupilsTests = new HashSet<PupilTest>();
    }

    public int Id { get; set; }        
    public ISet<PupilTest> PupilsTests { get; set; }

}
 

Миграция

  public partial class Init11 : Migration
    {
        protected override void Up(MigrationBuilder migrationBuilder)
        {
            migrationBuilder.DropForeignKey(
                name: "FK_PupilTests_Pupils_PupilId",
                table: "PupilTests");

            migrationBuilder.AddForeignKey(
                name: "FK_PupilTests_Pupils_PupilId",
                table: "PupilTests",
                column: "PupilId",
                principalTable: "Pupils",
                principalColumn: "Id",
                onDelete: ReferentialAction.Restrict);
        }

        protected override void Down(MigrationBuilder migrationBuilder)
        {
            migrationBuilder.DropForeignKey(
                name: "FK_PupilTests_Pupils_PupilId",
                table: "PupilTests");

            migrationBuilder.AddForeignKey(
                name: "FK_PupilTests_Pupils_PupilId",
                table: "PupilTests",
                column: "PupilId",
                principalTable: "Pupils",
                principalColumn: "Id",
                onDelete: ReferentialAction.Cascade);
        }
    }