How to Use Navigation Property generate left join sql not inner join sql

When Use Navigate Property one to one:

Normally the sql is a inner join , I do not know how to write a left Join use one to one Navigate Property

usually，we can also use Include to make ef generate a left join sql ,there is other method？

I donot like linq like this:

var LeftJoin = from a in aList
               join b in bList on a.Id equals b.Id into cc
               from b in cc.DefaultIfEmpty()

can implent like this?

      _context.Doctor.where(t=>t.Id==id)
                    .Select(doctor => new DoctorDTO()
                     {
                         Name=doctor.Name,
                        HospitalName=doctor.Hospital.Name  // want  left join  not innner join
                      }

In project ,i use automapper ProjectTo< DTO >,but how can i use One to One Navigation property generate left join sql?

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@ByZhouhang AFAIK EF Core does not generate RIGHT JOIN - it would be a bit difficult to imagine the LINQ that would be used to express such a query; you’ll have to start your LINQ query from UserAnswer. Note that RIGHT JOINs are mathematically rewritable as LEFT JOINs. Do you have any particular reason to want to start with UserAnswer rather than TrialQuestion, or is a matter of personal preference?

[roji]

@ByZhouhang as with your first code sample (Doctor and Hospital), if you make UserAnswer.TrialQuestionId nullable, EF Core will produce a LEFT JOIN, since a UserAnswer might not have a TrialQuestion; the “requiredness” of navigations is determined by the nullability of their foreign keys, and that’s what determines whether an INNER or LEFT join is used.

EF Core doesn’t generate RIGHT JOIN, but these are logically the same as LEFT JOIN.