Refs #33308 -- Enabled explicit GROUP BY and ORDER BY aliases.

This ensures explicit grouping from using values() before annotating an
aggregate function groups by selected aliases if supported.

The GROUP BY feature is disabled on Oracle because it doesn't support it.

django/db/backends/base/features.py

@@ -10,6 +10,7 @@ class BaseDatabaseFeatures:
     allows_group_by_lob = True
     allows_group_by_pk = False
     allows_group_by_selected_pks = False
+    allows_group_by_refs = True
     empty_fetchmany_value = []
     update_can_self_select = True
 

django/db/backends/oracle/features.py

@@ -8,6 +8,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
     # Oracle crashes with "ORA-00932: inconsistent datatypes: expected - got
     # BLOB" when grouping by LOBs (#24096).
     allows_group_by_lob = False
+    allows_group_by_refs = False
     interprets_empty_strings_as_nulls = True
     has_select_for_update = True
     has_select_for_update_nowait = True

django/db/models/expressions.py

@@ -419,6 +419,8 @@ class BaseExpression:
 
     def get_group_by_cols(self, alias=None):
         if not self.contains_aggregate:
+            if alias:
+                return [Ref(alias, self)]
             return [self]
         cols = []
         for source in self.get_source_expressions():
@@ -1243,7 +1245,7 @@ class ExpressionWrapper(SQLiteNumericMixin, Expression):
             return expression.get_group_by_cols(alias=alias)
         # For non-expressions e.g. an SQL WHERE clause, the entire
         # `expression` must be included in the GROUP BY clause.
-        return super().get_group_by_cols()
+        return super().get_group_by_cols(alias=alias)
 
     def as_sql(self, compiler, connection):
         return compiler.compile(self.expression)

django/db/models/sql/compiler.py

@@ -131,8 +131,11 @@ class SQLCompiler:
             # Converts string references to expressions.
             for expr in self.query.group_by:
                 if not hasattr(expr, "as_sql"):
-                    expressions.append(self.query.resolve_ref(expr))
+                    expr = self.query.resolve_ref(expr)
-                else:
+                if not self.connection.features.allows_group_by_refs and isinstance(
+                    expr, Ref
+                ):
+                    expr = expr.source
                 expressions.append(expr)
         # Note that even if the group_by is set, it is only the minimal
         # set to group by. So, we need to add cols in select, order_by, and
@@ -344,7 +347,13 @@ class SQLCompiler:
                 if not self.query.standard_ordering:
                     field = field.copy()
                     field.reverse_ordering()
-                yield field, False
+                if isinstance(field.expression, F) and (
+                    annotation := self.query.annotation_select.get(
+                        field.expression.name
+                    )
+                ):
+                    field.expression = Ref(field.expression.name, annotation)
+                yield field, isinstance(field.expression, Ref)
                 continue
             if field == "?":  # random
                 yield OrderBy(Random()), False
@@ -432,6 +441,10 @@ class SQLCompiler:
         """
         result = []
         seen = set()
+        replacements = {
+            expr: Ref(alias, expr)
+            for alias, expr in self.query.annotation_select.items()
+        }
 
         for expr, is_ref in self._order_by_pairs():
             resolved = expr.resolve_expression(self.query, allow_joins=True, reuse=None)
@@ -461,7 +474,7 @@ class SQLCompiler:
                         q.add_annotation(expr_src, col_name)
                     self.query.add_select_col(resolved, col_name)
                     resolved.set_source_expressions([RawSQL(f"{order_by_idx}", ())])
-            sql, params = self.compile(resolved)
+            sql, params = self.compile(resolved.replace_expressions(replacements))
             # Don't add the same column twice, but the order direction is
             # not taken into account so we strip it. When this entire method
             # is refactored into expressions, then we can check each part as we

django/db/models/sql/query.py

@@ -2220,8 +2220,8 @@ class Query(BaseExpression):
         primary key, and the query would be equivalent, the optimization
         will be made automatically.
         """
-        # Column names from JOINs to check collisions with aliases.
         if allow_aliases:
+            # Column names from JOINs to check collisions with aliases.
             column_names = set()
             seen_models = set()
             for join in list(self.alias_map.values())[1:]:  # Skip base table.
@@ -2231,7 +2231,20 @@ class Query(BaseExpression):
                         {field.column for field in model._meta.local_concrete_fields}
                     )
                     seen_models.add(model)
-
+            if self.values_select:
+                # If grouping by aliases is allowed assign selected values
+                # aliases by moving them to annotations.
+                group_by_annotations = {}
+                values_select = {}
+                for alias, expr in zip(self.values_select, self.select):
+                    if isinstance(expr, Col):
+                        values_select[alias] = expr
+                    else:
+                        group_by_annotations[alias] = expr
+                self.annotations = {**group_by_annotations, **self.annotations}
+                self.append_annotation_mask(group_by_annotations)
+                self.select = tuple(values_select.values())
+                self.values_select = tuple(values_select)
         group_by = list(self.select)
         if self.annotation_select:
             for alias, annotation in self.annotation_select.items():

tests/aggregation_regress/tests.py

@@ -178,10 +178,19 @@ class AggregationTests(TestCase):
             )
             .annotate(sum_discount=Sum("discount_price"))
         )
+        with self.assertNumQueries(1) as ctx:
             self.assertSequenceEqual(
                 values,
-            [{"discount_price": Decimal("59.38"), "sum_discount": Decimal("59.38")}],
+                [
+                    {
+                        "discount_price": Decimal("59.38"),
+                        "sum_discount": Decimal("59.38"),
+                    }
+                ],
             )
+        if connection.features.allows_group_by_refs:
+            alias = connection.ops.quote_name("discount_price")
+            self.assertIn(f"GROUP BY {alias}", ctx[0]["sql"])
 
     def test_aggregates_in_where_clause(self):
         """

tests/postgres_tests/test_array.py

@@ -12,7 +12,12 @@ from django.core.management import call_command
 from django.db import IntegrityError, connection, models
 from django.db.models.expressions import Exists, OuterRef, RawSQL, Value
 from django.db.models.functions import Cast, JSONObject, Upper
-from django.test import TransactionTestCase, modify_settings, override_settings
+from django.test import (
+    TransactionTestCase,
+    modify_settings,
+    override_settings,
+    skipUnlessDBFeature,
+)
 from django.test.utils import isolate_apps
 from django.utils import timezone
 
@@ -405,6 +410,27 @@ class TestQuerying(PostgreSQLTestCase):
                     expected,
                 )
 
+    @skipUnlessDBFeature("allows_group_by_refs")
+    def test_group_by_order_by_aliases(self):
+        with self.assertNumQueries(1) as ctx:
+            self.assertSequenceEqual(
+                NullableIntegerArrayModel.objects.filter(
+                    field__0__isnull=False,
+                )
+                .values("field__0")
+                .annotate(arrayagg=ArrayAgg("id"))
+                .order_by("field__0"),
+                [
+                    {"field__0": 1, "arrayagg": [1]},
+                    {"field__0": 2, "arrayagg": [2, 3]},
+                    {"field__0": 20, "arrayagg": [4]},
+                ],
+            )
+        alias = connection.ops.quote_name("field__0")
+        sql = ctx[0]["sql"]
+        self.assertIn(f"GROUP BY {alias}", sql)
+        self.assertIn(f"ORDER BY {alias}", sql)
+
     def test_index(self):
         self.assertSequenceEqual(
             NullableIntegerArrayModel.objects.filter(field__0=2), self.objs[1:3]