npgsql + efcore bug

Description

When doing an:

• include on a collection
• a join on that
• access a "computed" property on something in the join
• while also returning that "something" directly

The left join to get the include gets duplicated by N + 1 amount of times, where N is the amount of computed properties

Example

With the following linq:

await db.FirstEntities
    .Include(x => x.ToInclude)
    .Join(
        db.SecondEntities,
        first => first.SecondEntityId,
        second => second.FirstEntityId,
        (first, second) => new {
            first,
            haha1 = first.ComputedProperty1,
            haha2 = first.ComputedProperty2,
            haha3 = first.ComputedProperty3,
        }
    )
    .ToListAsync();

the generated SQL is:

SELECT f."Id", f."SecondEntityId", s."Id", f0."Id", f0."Col1", f0."Col2", f0."Col3", f0."Col4", f0."Col5", f0."FirstEntityId", s."FirstEntityId", f1."Id", f1."Col1", f1."Col2", f1."Col3", f1."Col4", f1."Col5", f1."FirstEnt
ityId", f2."Id", f2."Col1", f2."Col2", f2."Col3", f2."Col4", f2."Col5", f2."FirstEntityId", f3."Id", f3."Col1", f3."Col2", f3."Col3", f3."Col4", f3."Col5", f3."FirstEntityId"
      FROM "FirstEntities" AS f
      INNER JOIN "SecondEntities" AS s ON f."SecondEntityId" = s."FirstEntityId"
      LEFT JOIN "FirstEntityIncludes" AS f0 ON f."Id" = f0."FirstEntityId"
      LEFT JOIN "FirstEntityIncludes" AS f1 ON f."Id" = f1."FirstEntityId"
      LEFT JOIN "FirstEntityIncludes" AS f2 ON f."Id" = f2."FirstEntityId"
      LEFT JOIN "FirstEntityIncludes" AS f3 ON f."Id" = f3."FirstEntityId"
      ORDER BY f."Id", s."Id", f0."Id", f1."Id", f2."Id"

Issue link

npgsql/efcore.pg#2655