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Refs #28333 -- Added partial support for filtering against window functions. 

Adds support for joint predicates against window annotations through
subquery wrapping while maintaining errors for disjointed filter
attempts.

The "qualify" wording was used to refer to predicates against window
annotations as it's the name of a specialized Snowflake extension to
SQL that is to window functions what HAVING is to aggregates.

While not complete the implementation should cover most of the common
use cases for filtering against window functions without requiring
the complex subquery pushdown and predicate re-aliasing machinery to
deal with disjointed predicates against columns, aggregates, and window
functions.

A complete disjointed filtering implementation should likely be
deferred until proper QUALIFY support lands or the ORM gains a proper
subquery pushdown interface.
This commit is contained in:
Simon Charette 2022-08-10 08:22:01 -04:00 committed by Mariusz Felisiak
parent f3f9d03edf
commit f387d024fc
9 changed files with 489 additions and 67 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
django/db/backends/mysql/compiler.py
View File

@ -28,10 +28,13 @@ class SQLDeleteCompiler(compiler.SQLDeleteCompiler, SQLCompiler):
# the SQLDeleteCompiler's default implementation when multiple tables
# are involved since MySQL/MariaDB will generate a more efficient query
# plan than when using a subquery.
where, having = self.query.where.split_having()
if self.single_alias or having:
# DELETE FROM cannot be used when filtering against aggregates
# since it doesn't allow for GROUP BY and HAVING clauses.
where, having, qualify = self.query.where.split_having_qualify(
must_group_by=self.query.group_by is not None
)
if self.single_alias or having or qualify:
# DELETE FROM cannot be used when filtering against aggregates or
# window functions as it doesn't allow for GROUP BY/HAVING clauses
# and the subquery wrapping (necessary to emulate QUALIFY).
return super().as_sql()
result = [
"DELETE %s FROM"

15
django/db/models/expressions.py
View File

@ -836,6 +836,7 @@ class ResolvedOuterRef(F):
"""
contains_aggregate = False
contains_over_clause = False
def as_sql(self, *args, **kwargs):
raise ValueError(
@ -1210,6 +1211,12 @@ class OrderByList(Func):
return "", ()
return super().as_sql(*args, **kwargs)
def get_group_by_cols(self):
group_by_cols = []
for order_by in self.get_source_expressions():
group_by_cols.extend(order_by.get_group_by_cols())
return group_by_cols
@deconstructible(path="django.db.models.ExpressionWrapper")
class ExpressionWrapper(SQLiteNumericMixin, Expression):
@ -1631,7 +1638,6 @@ class Window(SQLiteNumericMixin, Expression):
# be introduced in the query as a result is not desired.
contains_aggregate = False
contains_over_clause = True
filterable = False
def __init__(
self,
@ -1733,7 +1739,12 @@ class Window(SQLiteNumericMixin, Expression):
return "<%s: %s>" % (self.__class__.__name__, self)
def get_group_by_cols(self, alias=None):
return []
group_by_cols = []
if self.partition_by:
group_by_cols.extend(self.partition_by.get_group_by_cols())
if self.order_by is not None:
group_by_cols.extend(self.order_by.get_group_by_cols())
return group_by_cols
class WindowFrame(Expression):

1
django/db/models/fields/related_lookups.py
View File

@ -14,6 +14,7 @@ from django.utils.deprecation import RemovedInDjango50Warning
class MultiColSource:
contains_aggregate = False
contains_over_clause = False
def __init__(self, alias, targets, sources, field):
self.targets, self.sources, self.field, self.alias = (

76
django/db/models/sql/compiler.py
View File

@ -9,6 +9,7 @@ from django.db import DatabaseError, NotSupportedError
from django.db.models.constants import LOOKUP_SEP
from django.db.models.expressions import F, OrderBy, RawSQL, Ref, Value
from django.db.models.functions import Cast, Random
from django.db.models.lookups import Lookup
from django.db.models.query_utils import select_related_descend
from django.db.models.sql.constants import (
CURSOR,
@ -73,7 +74,9 @@ class SQLCompiler:
"""
self.setup_query(with_col_aliases=with_col_aliases)
order_by = self.get_order_by()
self.where, self.having = self.query.where.split_having()
self.where, self.having, self.qualify = self.query.where.split_having_qualify(
must_group_by=self.query.group_by is not None
)
extra_select = self.get_extra_select(order_by, self.select)
self.has_extra_select = bool(extra_select)
group_by = self.get_group_by(self.select + extra_select, order_by)
@ -584,6 +587,74 @@ class SQLCompiler:
params.extend(part)
return result, params
def get_qualify_sql(self):
where_parts = []
if self.where:
where_parts.append(self.where)
if self.having:
where_parts.append(self.having)
inner_query = self.query.clone()
inner_query.subquery = True
inner_query.where = inner_query.where.__class__(where_parts)
# Augment the inner query with any window function references that
# might have been masked via values() and alias(). If any masked
# aliases are added they'll be masked again to avoid fetching
# the data in the `if qual_aliases` branch below.
select = {
expr: alias for expr, _, alias in self.get_select(with_col_aliases=True)[0]
}
qual_aliases = set()
replacements = {}
expressions = list(self.qualify.leaves())
while expressions:
expr = expressions.pop()
if select_alias := (select.get(expr) or replacements.get(expr)):
replacements[expr] = select_alias
elif isinstance(expr, Lookup):
expressions.extend(expr.get_source_expressions())
else:
num_qual_alias = len(qual_aliases)
select_alias = f"qual{num_qual_alias}"
qual_aliases.add(select_alias)
inner_query.add_annotation(expr, select_alias)
replacements[expr] = select_alias
self.qualify = self.qualify.replace_expressions(
{expr: Ref(alias, expr) for expr, alias in replacements.items()}
)
inner_query_compiler = inner_query.get_compiler(
self.using, elide_empty=self.elide_empty
)
inner_sql, inner_params = inner_query_compiler.as_sql(
# The limits must be applied to the outer query to avoid pruning
# results too eagerly.
with_limits=False,
# Force unique aliasing of selected columns to avoid collisions
# and make rhs predicates referencing easier.
with_col_aliases=True,
)
qualify_sql, qualify_params = self.compile(self.qualify)
result = [
"SELECT * FROM (",
inner_sql,
")",
self.connection.ops.quote_name("qualify"),
"WHERE",
qualify_sql,
]
if qual_aliases:
# If some select aliases were unmasked for filtering purposes they
# must be masked back.
cols = [self.connection.ops.quote_name(alias) for alias in select.values()]
result = [
"SELECT",
", ".join(cols),
"FROM (",
*result,
")",
self.connection.ops.quote_name("qualify_mask"),
]
return result, list(inner_params) + qualify_params
def as_sql(self, with_limits=True, with_col_aliases=False):
"""
Create the SQL for this query. Return the SQL string and list of
@ -614,6 +685,9 @@ class SQLCompiler:
result, params = self.get_combinator_sql(
combinator, self.query.combinator_all
)
elif self.qualify:
result, params = self.get_qualify_sql()
order_by = None
else:
distinct_fields, distinct_params = self.get_distinct()
# This must come after 'select', 'ordering', and 'distinct'

99
django/db/models/sql/where.py
View File

@ -35,48 +35,81 @@ class WhereNode(tree.Node):
resolved = False
conditional = True
def split_having(self, negated=False):
def split_having_qualify(self, negated=False, must_group_by=False):
"""
Return two possibly None nodes: one for those parts of self that
should be included in the WHERE clause and one for those parts of
self that must be included in the HAVING clause.
Return three possibly None nodes: one for those parts of self that
should be included in the WHERE clause, one for those parts of self
that must be included in the HAVING clause, and one for those parts
that refer to window functions.
"""
if not self.contains_aggregate:
return self, None
if not self.contains_aggregate and not self.contains_over_clause:
return self, None, None
in_negated = negated ^ self.negated
# If the effective connector is OR or XOR and this node contains an
# aggregate, then we need to push the whole branch to HAVING clause.
may_need_split = (
# Whether or not children must be connected in the same filtering
# clause (WHERE > HAVING > QUALIFY) to maintain logical semantic.
must_remain_connected = (
(in_negated and self.connector == AND)
or (not in_negated and self.connector == OR)
or self.connector == XOR
)
if may_need_split and self.contains_aggregate:
return None, self
if (
must_remain_connected
and self.contains_aggregate
and not self.contains_over_clause
):
# It's must cheaper to short-circuit and stash everything in the
# HAVING clause than split children if possible.
return None, self, None
where_parts = []
having_parts = []
qualify_parts = []
for c in self.children:
if hasattr(c, "split_having"):
where_part, having_part = c.split_having(in_negated)
if hasattr(c, "split_having_qualify"):
where_part, having_part, qualify_part = c.split_having_qualify(
in_negated, must_group_by
)
if where_part is not None:
where_parts.append(where_part)
if having_part is not None:
having_parts.append(having_part)
if qualify_part is not None:
qualify_parts.append(qualify_part)
elif c.contains_over_clause:
qualify_parts.append(c)
elif c.contains_aggregate:
having_parts.append(c)
else:
where_parts.append(c)
having_node = (
self.create(having_parts, self.connector, self.negated)
if having_parts
else None
)
if must_remain_connected and qualify_parts:
# Disjunctive heterogeneous predicates can be pushed down to
# qualify as long as no conditional aggregation is involved.
if not where_parts or (where_parts and not must_group_by):
return None, None, self
elif where_parts:
# In theory this should only be enforced when dealing with
# where_parts containing predicates against multi-valued
# relationships that could affect aggregation results but this
# is complex to infer properly.
raise NotImplementedError(
"Heterogeneous disjunctive predicates against window functions are "
"not implemented when performing conditional aggregation."
)
where_node = (
self.create(where_parts, self.connector, self.negated)
if where_parts
else None
)
return where_node, having_node
having_node = (
self.create(having_parts, self.connector, self.negated)
if having_parts
else None
)
qualify_node = (
self.create(qualify_parts, self.connector, self.negated)
if qualify_parts
else None
)
return where_node, having_node, qualify_node
def as_sql(self, compiler, connection):
"""
@ -183,6 +216,14 @@ class WhereNode(tree.Node):
clone.relabel_aliases(change_map)
return clone
def replace_expressions(self, replacements):
if replacement := replacements.get(self):
return replacement
clone = self.create(connector=self.connector, negated=self.negated)
for child in self.children:
clone.children.append(child.replace_expressions(replacements))
return clone
@classmethod
def _contains_aggregate(cls, obj):
if isinstance(obj, tree.Node):
@ -231,6 +272,10 @@ class WhereNode(tree.Node):
return BooleanField()
@property
def _output_field_or_none(self):
return self.output_field
def select_format(self, compiler, sql, params):
# Wrap filters with a CASE WHEN expression if a database backend
# (e.g. Oracle) doesn't support boolean expression in SELECT or GROUP
@ -245,19 +290,28 @@ class WhereNode(tree.Node):
def get_lookup(self, lookup):
return self.output_field.get_lookup(lookup)
def leaves(self):
for child in self.children:
if isinstance(child, WhereNode):
yield from child.leaves()
else:
yield child
class NothingNode:
"""A node that matches nothing."""
contains_aggregate = False
contains_over_clause = False
def as_sql(self, compiler=None, connection=None):
raise EmptyResultSet
class ExtraWhere:
# The contents are a black box - assume no aggregates are used.
# The contents are a black box - assume no aggregates or windows are used.
contains_aggregate = False
contains_over_clause = False
def __init__(self, sqls, params):
self.sqls = sqls
@ -269,9 +323,10 @@ class ExtraWhere:
class SubqueryConstraint:
# Even if aggregates would be used in a subquery, the outer query isn't
# interested about those.
# Even if aggregates or windows would be used in a subquery,
# the outer query isn't interested about those.
contains_aggregate = False
contains_over_clause = False
def __init__(self, alias, columns, targets, query_object):
self.alias = alias

31
docs/ref/models/expressions.txt
View File

@ -741,12 +741,6 @@ instead they are part of the selected columns.
.. class:: Window(expression, partition_by=None, order_by=None, frame=None, output_field=None)
.. attribute:: filterable
Defaults to ``False``. The SQL standard disallows referencing window
functions in the ``WHERE`` clause and Django raises an exception when
constructing a ``QuerySet`` that would do that.
.. attribute:: template
Defaults to ``%(expression)s OVER (%(window)s)'``. If only the
@ -819,6 +813,31 @@ to reduce repetition::
>>> ),
>>> )
Filtering against window functions is supported as long as lookups are not
disjunctive (not using ``OR`` or ``XOR`` as a connector) and against a queryset
performing aggregation.
For example, a query that relies on aggregation and has an ``OR``-ed filter
against a window function and a field is not supported. Applying combined
predicates post-aggregation could cause rows that would normally be excluded
from groups to be included::
>>> qs = Movie.objects.annotate(
>>> category_rank=Window(
>>> Rank(), partition_by='category', order_by='-rating'
>>> ),
>>> scenes_count=Count('actors'),
>>> ).filter(
>>> Q(category_rank__lte=3) | Q(title__contains='Batman')
>>> )
>>> list(qs)
NotImplementedError: Heterogeneous disjunctive predicates against window functions
are not implemented when performing conditional aggregation.
.. versionchanged:: 4.2
Support for filtering against window functions was added.
Among Django's built-in database backends, MySQL 8.0.2+, PostgreSQL, and Oracle
support window expressions. Support for different window expression features
varies among the different databases. For example, the options in

4
docs/releases/4.2.txt
View File

@ -189,7 +189,9 @@ Migrations
Models
~~~~~~
* ...
* ``QuerySet`` now extensively supports filtering against
:ref:`window-functions` with the exception of disjunctive filter lookups
against window functions when performing aggregation.
Requests and Responses
~~~~~~~~~~~~~~~~~~~~~~

7
tests/expressions_window/models.py
View File

@ -17,6 +17,13 @@ class Employee(models.Model):
bonus = models.DecimalField(decimal_places=2, max_digits=15, null=True)
class PastEmployeeDepartment(models.Model):
employee = models.ForeignKey(
Employee, related_name="past_departments", on_delete=models.CASCADE
)
department = models.CharField(max_length=40, blank=False, null=False)
class Detail(models.Model):
value = models.JSONField()

312
tests/expressions_window/tests.py
View File

@ -6,10 +6,9 @@ from django.core.exceptions import FieldError
from django.db import NotSupportedError, connection
from django.db.models import (
Avg,
BooleanField,
Case,
Count,
F,
Func,
IntegerField,
Max,
Min,
@ -41,15 +40,17 @@ from django.db.models.functions import (
RowNumber,
Upper,
)
from django.db.models.lookups import Exact
from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
from .models import Detail, Employee
from .models import Classification, Detail, Employee, PastEmployeeDepartment
@skipUnlessDBFeature("supports_over_clause")
class WindowFunctionTests(TestCase):
@classmethod
def setUpTestData(cls):
classification = Classification.objects.create()
Employee.objects.bulk_create(
[
Employee(
@ -59,6 +60,7 @@ class WindowFunctionTests(TestCase):
hire_date=e[3],
age=e[4],
bonus=Decimal(e[1]) / 400,
classification=classification,
)
for e in [
("Jones", 45000, "Accounting", datetime.datetime(2005, 11, 1), 20),
@ -82,6 +84,13 @@ class WindowFunctionTests(TestCase):
]
]
)
employees = list(Employee.objects.order_by("pk"))
PastEmployeeDepartment.objects.bulk_create(
[
PastEmployeeDepartment(employee=employees[6], department="Sales"),
PastEmployeeDepartment(employee=employees[10], department="IT"),
]
)
def test_dense_rank(self):
tests = [
@ -902,6 +911,263 @@ class WindowFunctionTests(TestCase):
)
self.assertEqual(qs.count(), 12)
def test_filter(self):
qs = Employee.objects.annotate(
department_salary_rank=Window(
Rank(), partition_by="department", order_by="-salary"
),
department_avg_age_diff=(
Window(Avg("age"), partition_by="department") - F("age")
),
).order_by("department", "name")
# Direct window reference.
self.assertQuerysetEqual(
qs.filter(department_salary_rank=1),
["Adams", "Wilkinson", "Miller", "Johnson", "Smith"],
lambda employee: employee.name,
)
# Through a combined expression containing a window.
self.assertQuerysetEqual(
qs.filter(department_avg_age_diff__gt=0),
["Jenson", "Jones", "Williams", "Miller", "Smith"],
lambda employee: employee.name,
)
# Intersection of multiple windows.
self.assertQuerysetEqual(
qs.filter(department_salary_rank=1, department_avg_age_diff__gt=0),
["Miller"],
lambda employee: employee.name,
)
# Union of multiple windows.
self.assertQuerysetEqual(
qs.filter(Q(department_salary_rank=1) | Q(department_avg_age_diff__gt=0)),
[
"Adams",
"Jenson",
"Jones",
"Williams",
"Wilkinson",
"Miller",
"Johnson",
"Smith",
"Smith",
],
lambda employee: employee.name,
)
def test_filter_conditional_annotation(self):
qs = (
Employee.objects.annotate(
rank=Window(Rank(), partition_by="department", order_by="-salary"),
case_first_rank=Case(
When(rank=1, then=True),
default=False,
),
q_first_rank=Q(rank=1),
)
.order_by("name")
.values_list("name", flat=True)
)
for annotation in ["case_first_rank", "q_first_rank"]:
with self.subTest(annotation=annotation):
self.assertSequenceEqual(
qs.filter(**{annotation: True}),
["Adams", "Johnson", "Miller", "Smith", "Wilkinson"],
)
def test_filter_conditional_expression(self):
qs = (
Employee.objects.filter(
Exact(Window(Rank(), partition_by="department", order_by="-salary"), 1)
)
.order_by("name")
.values_list("name", flat=True)
)
self.assertSequenceEqual(
qs, ["Adams", "Johnson", "Miller", "Smith", "Wilkinson"]
)
def test_filter_column_ref_rhs(self):
qs = (
Employee.objects.annotate(
max_dept_salary=Window(Max("salary"), partition_by="department")
)
.filter(max_dept_salary=F("salary"))
.order_by("name")
.values_list("name", flat=True)
)
self.assertSequenceEqual(
qs, ["Adams", "Johnson", "Miller", "Smith", "Wilkinson"]
)
def test_filter_values(self):
qs = (
Employee.objects.annotate(
department_salary_rank=Window(
Rank(), partition_by="department", order_by="-salary"
),
)
.order_by("department", "name")
.values_list(Upper("name"), flat=True)
)
self.assertSequenceEqual(
qs.filter(department_salary_rank=1),
["ADAMS", "WILKINSON", "MILLER", "JOHNSON", "SMITH"],
)
def test_filter_alias(self):
qs = Employee.objects.alias(
department_avg_age_diff=(
Window(Avg("age"), partition_by="department") - F("age")
),
).order_by("department", "name")
self.assertQuerysetEqual(
qs.filter(department_avg_age_diff__gt=0),
["Jenson", "Jones", "Williams", "Miller", "Smith"],
lambda employee: employee.name,
)
def test_filter_select_related(self):
qs = (
Employee.objects.alias(
department_avg_age_diff=(
Window(Avg("age"), partition_by="department") - F("age")
),
)
.select_related("classification")
.filter(department_avg_age_diff__gt=0)
.order_by("department", "name")
)
self.assertQuerysetEqual(
qs,
["Jenson", "Jones", "Williams", "Miller", "Smith"],
lambda employee: employee.name,
)
with self.assertNumQueries(0):
qs[0].classification
def test_exclude(self):
qs = Employee.objects.annotate(
department_salary_rank=Window(
Rank(), partition_by="department", order_by="-salary"
),
department_avg_age_diff=(
Window(Avg("age"), partition_by="department") - F("age")
),
).order_by("department", "name")
# Direct window reference.
self.assertQuerysetEqual(
qs.exclude(department_salary_rank__gt=1),
["Adams", "Wilkinson", "Miller", "Johnson", "Smith"],
lambda employee: employee.name,
)
# Through a combined expression containing a window.
self.assertQuerysetEqual(
qs.exclude(department_avg_age_diff__lte=0),
["Jenson", "Jones", "Williams", "Miller", "Smith"],
lambda employee: employee.name,
)
# Union of multiple windows.
self.assertQuerysetEqual(
qs.exclude(
Q(department_salary_rank__gt=1) | Q(department_avg_age_diff__lte=0)
),
["Miller"],
lambda employee: employee.name,
)
# Intersection of multiple windows.
self.assertQuerysetEqual(
qs.exclude(department_salary_rank__gt=1, department_avg_age_diff__lte=0),
[
"Adams",
"Jenson",
"Jones",
"Williams",
"Wilkinson",
"Miller",
"Johnson",
"Smith",
"Smith",
],
lambda employee: employee.name,
)
def test_heterogeneous_filter(self):
qs = (
Employee.objects.annotate(
department_salary_rank=Window(
Rank(), partition_by="department", order_by="-salary"
),
)
.order_by("name")
.values_list("name", flat=True)
)
# Heterogeneous filter between window function and aggregates pushes
# the WHERE clause to the QUALIFY outer query.
self.assertSequenceEqual(
qs.filter(
department_salary_rank=1, department__in=["Accounting", "Management"]
),
["Adams", "Miller"],
)
self.assertSequenceEqual(
qs.filter(
Q(department_salary_rank=1)
| Q(department__in=["Accounting", "Management"])
),
[
"Adams",
"Jenson",
"Johnson",
"Johnson",
"Jones",
"Miller",
"Smith",
"Wilkinson",
"Williams",
],
)
# Heterogeneous filter between window function and aggregates pushes
# the HAVING clause to the QUALIFY outer query.
qs = qs.annotate(past_department_count=Count("past_departments"))
self.assertSequenceEqual(
qs.filter(department_salary_rank=1, past_department_count__gte=1),
["Johnson", "Miller"],
)
self.assertSequenceEqual(
qs.filter(Q(department_salary_rank=1) | Q(past_department_count__gte=1)),
["Adams", "Johnson", "Miller", "Smith", "Wilkinson"],
)
def test_limited_filter(self):
"""
A query filtering against a window function have its limit applied
after window filtering takes place.
"""
self.assertQuerysetEqual(
Employee.objects.annotate(
department_salary_rank=Window(
Rank(), partition_by="department", order_by="-salary"
)
)
.filter(department_salary_rank=1)
.order_by("department")[0:3],
["Adams", "Wilkinson", "Miller"],
lambda employee: employee.name,
)
def test_filter_count(self):
self.assertEqual(
Employee.objects.annotate(
department_salary_rank=Window(
Rank(), partition_by="department", order_by="-salary"
)
)
.filter(department_salary_rank=1)
.count(),
5,
)
@skipUnlessDBFeature("supports_frame_range_fixed_distance")
def test_range_n_preceding_and_following(self):
qs = Employee.objects.annotate(
@ -1071,6 +1337,7 @@ class WindowFunctionTests(TestCase):
),
year=ExtractYear("hire_date"),
)
.filter(sum__gte=45000)
.values("year", "sum")
.distinct("year")
.order_by("year")
@ -1081,7 +1348,6 @@ class WindowFunctionTests(TestCase):
{"year": 2008, "sum": 45000},
{"year": 2009, "sum": 128000},
{"year": 2011, "sum": 60000},
{"year": 2012, "sum": 40000},
{"year": 2013, "sum": 84000},
]
for idx, val in zip(range(len(results)), results):
@ -1348,34 +1614,18 @@ class NonQueryWindowTests(SimpleTestCase):
frame.window_frame_start_end(None, None, None)
def test_invalid_filter(self):
msg = "Window is disallowed in the filter clause"
qs = Employee.objects.annotate(dense_rank=Window(expression=DenseRank()))
with self.assertRaisesMessage(NotSupportedError, msg):
qs.filter(dense_rank__gte=1)
with self.assertRaisesMessage(NotSupportedError, msg):
qs.annotate(inc_rank=F("dense_rank") + Value(1)).filter(inc_rank__gte=1)
with self.assertRaisesMessage(NotSupportedError, msg):
qs.filter(id=F("dense_rank"))
with self.assertRaisesMessage(NotSupportedError, msg):
qs.filter(id=Func("dense_rank", 2, function="div"))
with self.assertRaisesMessage(NotSupportedError, msg):
qs.annotate(total=Sum("dense_rank", filter=Q(name="Jones"))).filter(total=1)
def test_conditional_annotation(self):
qs = Employee.objects.annotate(
dense_rank=Window(expression=DenseRank()),
).annotate(
equal=Case(
When(id=F("dense_rank"), then=Value(True)),
default=Value(False),
output_field=BooleanField(),
),
msg = (
"Heterogeneous disjunctive predicates against window functions are not "
"implemented when performing conditional aggregation."
)
# The SQL standard disallows referencing window functions in the WHERE
# clause.
msg = "Window is disallowed in the filter clause"
with self.assertRaisesMessage(NotSupportedError, msg):
qs.filter(equal=True)
qs = Employee.objects.annotate(
window=Window(Rank()),
past_dept_cnt=Count("past_departments"),
)
with self.assertRaisesMessage(NotImplementedError, msg):
list(qs.filter(Q(window=1) | Q(department="Accounting")))
with self.assertRaisesMessage(NotImplementedError, msg):
list(qs.exclude(window=1, department="Accounting"))
def test_invalid_order_by(self):
msg = (