You've created both a one-to-one relationship
(by convention) and two one-to-many relationships
(by configuration). That's definitely not correct.
Based on your description, you need:
public class BuySellHouse
{
public int Id { get; set; }
public int? EstateImagesId { get; set; }
public EstateImages EstateImages { get; set; }
}
public class EstateImages
{
public int Id { get; set; }
public int BuySellHouseId { get; set; }
public BuySellHouse BuySellHouse { get; set; }
}
public class BuySellHouseConfig : EntityTypeConfiguration<BuySellHouse>
{
public BuySellHouseConfig()
{
HasKey(x => x.Id);
Property(x => x.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
ToTable("BuySellHouse");
}
}
public class EstateImagesConfig : EntityTypeConfiguration<EstateImages>
{
public EstateImagesConfig()
{
HasKey(x => x.Id);
Property(x => x.Id).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
ToTable("EstateImages");
HasRequired(x => x.BuySellHouse).WithOptional(x => x.EstateImages).WillCascadeOnDelete(true);
}
}
Fluent API - Relationships - EF6 | Microsoft Docs[
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