[1.8.x] Fixed #12768 -- Fixed QuerySet.raw() regression on FK with custom db_column.

Backport of e063ac2fae from master

django/db/models/query.py

@@ -1267,11 +1267,11 @@ class RawQuerySet(object):
         """
         Resolve the init field names and value positions
         """
-        model_init_names = [f.attname for f in self.model._meta.fields
-                            if f.attname in self.columns]
+        model_init_fields = [f for f in self.model._meta.fields if f.column in self.columns]
         annotation_fields = [(column, pos) for pos, column in enumerate(self.columns)
                              if column not in self.model_fields]
-        model_init_order = [self.columns.index(fname) for fname in model_init_names]
+        model_init_order = [self.columns.index(f.column) for f in model_init_fields]
+        model_init_names = [f.attname for f in model_init_fields]
         return model_init_names, model_init_order, annotation_fields
 
     def __iter__(self):

docs/releases/1.8.4.txt

@@ -14,3 +14,7 @@ Bugfixes
 
 * Added a system check warning if the old ``TEMPLATE_*`` settings are defined
   in addition to the new ``TEMPLATES`` setting.
+
+* Fixed ``QuerySet.raw()`` so ``InvalidQuery`` is not raised when using the
+  ``db_column`` name of a ``ForeignKey`` field with ``primary_key=True``
+  (:ticket:`12768`).

tests/raw_query/models.py

@@ -23,6 +23,10 @@ class Book(models.Model):
     opening_line = models.TextField()
 
 
+class BookFkAsPk(models.Model):
+    book = models.ForeignKey(Book, primary_key=True, db_column="not_the_default")
+
+
 class Coffee(models.Model):
     brand = models.CharField(max_length=255, db_column="name")
 

tests/raw_query/tests.py

@@ -5,7 +5,7 @@ from datetime import date
 from django.db.models.query_utils import InvalidQuery
 from django.test import TestCase, skipUnlessDBFeature
 
-from .models import Author, Book, Coffee, FriendlyAuthor, Reviewer
+from .models import Author, Book, BookFkAsPk, Coffee, FriendlyAuthor, Reviewer
 
 
 class RawQueryTests(TestCase):
@@ -259,3 +259,15 @@ class RawQueryTests(TestCase):
             list(Book.objects.raw('SELECT id FROM (SELECT * FROM raw_query_book WHERE paperback IS NOT NULL) sq'))
         except InvalidQuery:
             self.fail("Using a subquery in a RawQuerySet raised InvalidQuery")
+
+    def test_db_column_name_is_used_in_raw_query(self):
+        """
+        Regression test that ensures the `column` attribute on the field is
+        used to generate the list of fields included in the query, as opposed
+        to the `attname`. This is important when the primary key is a
+        ForeignKey field because `attname` and `column` are not necessarily the
+        same.
+        """
+        b1 = Book.objects.latest('id')
+        b = BookFkAsPk.objects.create(book=b1)
+        self.assertEqual(list(BookFkAsPk.objects.raw('SELECT not_the_default FROM raw_query_bookfkaspk')), [b])