Update on a single record caused cascade update on entire table, setting all foreign key fields to NULL when upgrading from 3.0 to 7.0

[stepheneire]

Bug description

Hi Team,

Recently when updating from EF Core 3.0 to EF Core 7.0 we discovered a bug that ended up setting millions for foreign key values to NULL. We discovered that a previously supported strategy of disabling the reverse foreign key collections is no longer supported but does not return a runtime error, which it should. Below is the code that set all the foreign keys to NULL.

Your code

var firearm = _dbContext.Firearms
                .Include(x => x.MakeNav)
                .First(x => x.Id == 1);

            firearm.FirStatId = 1;
                
            await _dbContext.SaveChangesAsync(cancellationToken); // This set all the Makes to NULL

This was the strategy we previously used (.Net 3.0) to disable the reverse foreign key collections.
            entity.HasOne(d => d.MakeNav)
                .WithOne()
                .HasForeignKey<Firearms>(d => d.MakeCode)
                .HasConstraintName("FIREARM_FIREARM_MAKE_FK");

Stack traces

Verbose output

EF Core version

7.0.0

Database provider

Oracle.EntityFrameworkCore

Target framework

.NET 8

Operating system

No response

IDE

No response

[AndriySvyryd]

Can you also include the referenced types and share a small runnable console project?