Checking parameter for null causes incorrect projections translation

[elementum]

Hello,

When checking a joined entity for NULL the further projecting of joined table does not take effect causing always selecting all fields and all subsequent joins if any.

Suppose having following entity hierarchy: User -> Job? -> Address

class User {
  public long Id { get; set; }
  public long? JobId { get; set; }
  // other unrelated properties
}

class Job {
 public long Id { get; set; }
 public long AddressId { get; set; }
 // other unrelated properties
}

class Address {
 public long Id { get; set; }
 // other unrelated properties
}

The following linq query

        var claim = await users
            .Select(x => new
            {
                x.Id,
                Job = x.Job == null ? null : new
                {
                    x.Job.Id,
                    Address = new
                    {
                        x.Job.Address.Id,
                        x.Job.Address.Street
                    }
                }
            })
            .Select(x => new
            {
                x.Id,
                Job = x.Job == null ? null : new
                {
                    x.Job.Id
                }
            })
            .Where(x => x.Id == 14501)
            .FirstOrDefaultAsync();

produces this sql:

SELECT c."Id", c0."Id", FALSE, c1."Id", c1."Street"
FROM "User" AS c
INNER JOIN "Job" AS c0 ON c."JobId" = c0."Id"
INNER JOIN "Address" AS c1 ON c0."AddressId" = c1."Id"
WHERE c."Id" = 14501

It includes join to Address table, even though it is not selected in the last Select method.

You may ask why doing consequent selects, the answer is the part before second select may come from elsewhere as IQueryable which you want to further narrow down.

Anyways, is that expected? And is it possible to workaround?

Environment

Target Framework: net8.0
Npgsql.EntityFrameworkCore.PostgreSQL: 8.0.4

[roji]

Can you please try this with 9.0 rc1? We've done some work on pruning unneeded bound which might solve this.

If you're still seeing this in 9.0, can you please reopen this issue in the EF repo, as it's very unlikely to be PG-specific?

[elementum]

FYI, same for 9.0

[elementum]

dotnet/efcore#35518