Fixed #30916 -- Added support for functional unique constraints.

Thanks Ian Foote and Mariusz Felisiak for reviews.
This commit is contained in:
Hannes Ljungberg 2021-02-06 20:45:54 +01:00 committed by Mariusz Felisiak
parent 19ce1d493a
commit 3aa545281e
15 changed files with 779 additions and 38 deletions

View File

@ -1184,16 +1184,16 @@ class BaseDatabaseSchemaEditor:
def _unique_sql(
self, model, fields, name, condition=None, deferrable=None,
include=None, opclasses=None,
include=None, opclasses=None, expressions=None,
):
if (
deferrable and
not self.connection.features.supports_deferrable_unique_constraints
):
return None
if condition or include or opclasses:
# Databases support conditional and covering unique constraints via
# a unique index.
if condition or include or opclasses or expressions:
# Databases support conditional, covering, and functional unique
# constraints via a unique index.
sql = self._create_unique_sql(
model,
fields,
@ -1201,6 +1201,7 @@ class BaseDatabaseSchemaEditor:
condition=condition,
include=include,
opclasses=opclasses,
expressions=expressions,
)
if sql:
self.deferred_sql.append(sql)
@ -1216,7 +1217,7 @@ class BaseDatabaseSchemaEditor:
def _create_unique_sql(
self, model, columns, name=None, condition=None, deferrable=None,
include=None, opclasses=None,
include=None, opclasses=None, expressions=None,
):
if (
(
@ -1224,23 +1225,28 @@ class BaseDatabaseSchemaEditor:
not self.connection.features.supports_deferrable_unique_constraints
) or
(condition and not self.connection.features.supports_partial_indexes) or
(include and not self.connection.features.supports_covering_indexes)
(include and not self.connection.features.supports_covering_indexes) or
(expressions and not self.connection.features.supports_expression_indexes)
):
return None
def create_unique_name(*args, **kwargs):
return self.quote_name(self._create_index_name(*args, **kwargs))
compiler = Query(model, alias_cols=False).get_compiler(connection=self.connection)
table = Table(model._meta.db_table, self.quote_name)
if name is None:
name = IndexName(model._meta.db_table, columns, '_uniq', create_unique_name)
else:
name = self.quote_name(name)
columns = self._index_columns(table, columns, col_suffixes=(), opclasses=opclasses)
if condition or include or opclasses:
if condition or include or opclasses or expressions:
sql = self.sql_create_unique_index
else:
sql = self.sql_create_unique
if columns:
columns = self._index_columns(table, columns, col_suffixes=(), opclasses=opclasses)
else:
columns = Expressions(model._meta.db_table, expressions, compiler, self.quote_value)
return Statement(
sql,
table=table,
@ -1253,7 +1259,7 @@ class BaseDatabaseSchemaEditor:
def _delete_unique_sql(
self, model, name, condition=None, deferrable=None, include=None,
opclasses=None,
opclasses=None, expressions=None,
):
if (
(
@ -1261,10 +1267,12 @@ class BaseDatabaseSchemaEditor:
not self.connection.features.supports_deferrable_unique_constraints
) or
(condition and not self.connection.features.supports_partial_indexes) or
(include and not self.connection.features.supports_covering_indexes)
(include and not self.connection.features.supports_covering_indexes) or
(expressions and not self.connection.features.supports_expression_indexes)
):
return None
if condition or include or opclasses:
if condition or include or opclasses or expressions:
sql = self.sql_delete_index
else:
sql = self.sql_delete_unique

View File

@ -289,7 +289,7 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
constraints[index] = {
'columns': OrderedSet(),
'primary_key': False,
'unique': False,
'unique': not non_unique,
'check': False,
'foreign_key': None,
}

View File

@ -307,6 +307,7 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
SELECT
ind.index_name,
LOWER(ind.index_type),
LOWER(ind.uniqueness),
LISTAGG(LOWER(cols.column_name), ',') WITHIN GROUP (ORDER BY cols.column_position),
LISTAGG(cols.descend, ',') WITHIN GROUP (ORDER BY cols.column_position)
FROM
@ -318,13 +319,13 @@ class DatabaseIntrospection(BaseDatabaseIntrospection):
FROM user_constraints cons
WHERE ind.index_name = cons.index_name
) AND cols.index_name = ind.index_name
GROUP BY ind.index_name, ind.index_type
GROUP BY ind.index_name, ind.index_type, ind.uniqueness
""", [table_name])
for constraint, type_, columns, orders in cursor.fetchall():
for constraint, type_, unique, columns, orders in cursor.fetchall():
constraint = self.identifier_converter(constraint)
constraints[constraint] = {
'primary_key': False,
'unique': False,
'unique': unique == 'unique',
'foreign_key': None,
'check': False,
'index': True,

View File

@ -419,13 +419,17 @@ class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
self.delete_model(old_field.remote_field.through)
def add_constraint(self, model, constraint):
if isinstance(constraint, UniqueConstraint) and constraint.condition:
if isinstance(constraint, UniqueConstraint) and (
constraint.condition or constraint.contains_expressions
):
super().add_constraint(model, constraint)
else:
self._remake_table(model)
def remove_constraint(self, model, constraint):
if isinstance(constraint, UniqueConstraint) and constraint.condition:
if isinstance(constraint, UniqueConstraint) and (
constraint.condition or constraint.contains_expressions
):
super().remove_constraint(model, constraint)
else:
self._remake_table(model)

View File

@ -2039,6 +2039,25 @@ class Model(metaclass=ModelBase):
id='models.W039',
)
)
if not (
connection.features.supports_expression_indexes or
'supports_expression_indexes' in cls._meta.required_db_features
) and any(
isinstance(constraint, UniqueConstraint) and constraint.contains_expressions
for constraint in cls._meta.constraints
):
errors.append(
checks.Warning(
'%s does not support unique constraints on '
'expressions.' % connection.display_name,
hint=(
"A constraint won't be created. Silence this "
"warning if you don't care about it."
),
obj=cls,
id='models.W044',
)
)
fields = set(chain.from_iterable(
(*constraint.fields, *constraint.include)
for constraint in cls._meta.constraints if isinstance(constraint, UniqueConstraint)
@ -2051,6 +2070,12 @@ class Model(metaclass=ModelBase):
'supports_partial_indexes' not in cls._meta.required_db_features
) and isinstance(constraint.condition, Q):
references.update(cls._get_expr_references(constraint.condition))
if (
connection.features.supports_expression_indexes or
'supports_expression_indexes' not in cls._meta.required_db_features
) and constraint.contains_expressions:
for expression in constraint.expressions:
references.update(cls._get_expr_references(expression))
elif isinstance(constraint, CheckConstraint):
if (
connection.features.supports_table_check_constraints or

View File

@ -1,5 +1,7 @@
from enum import Enum
from django.db.models.expressions import ExpressionList, F
from django.db.models.indexes import IndexExpression
from django.db.models.query_utils import Q
from django.db.models.sql.query import Query
@ -10,6 +12,10 @@ class BaseConstraint:
def __init__(self, name):
self.name = name
@property
def contains_expressions(self):
return False
def constraint_sql(self, model, schema_editor):
raise NotImplementedError('This method must be implemented by a subclass.')
@ -83,16 +89,25 @@ class Deferrable(Enum):
class UniqueConstraint(BaseConstraint):
def __init__(
self,
*,
fields,
name,
*expressions,
fields=(),
name=None,
condition=None,
deferrable=None,
include=None,
opclasses=(),
):
if not fields:
raise ValueError('At least one field is required to define a unique constraint.')
if not name:
raise ValueError('A unique constraint must be named.')
if not expressions and not fields:
raise ValueError(
'At least one field or expression is required to define a '
'unique constraint.'
)
if expressions and fields:
raise ValueError(
'UniqueConstraint.fields and expressions are mutually exclusive.'
)
if not isinstance(condition, (type(None), Q)):
raise ValueError('UniqueConstraint.condition must be a Q instance.')
if condition and deferrable:
@ -107,6 +122,15 @@ class UniqueConstraint(BaseConstraint):
raise ValueError(
'UniqueConstraint with opclasses cannot be deferred.'
)
if expressions and deferrable:
raise ValueError(
'UniqueConstraint with expressions cannot be deferred.'
)
if expressions and opclasses:
raise ValueError(
'UniqueConstraint.opclasses cannot be used with expressions. '
'Use django.contrib.postgres.indexes.OpClass() instead.'
)
if not isinstance(deferrable, (type(None), Deferrable)):
raise ValueError(
'UniqueConstraint.deferrable must be a Deferrable instance.'
@ -125,8 +149,16 @@ class UniqueConstraint(BaseConstraint):
self.deferrable = deferrable
self.include = tuple(include) if include else ()
self.opclasses = opclasses
self.expressions = tuple(
F(expression) if isinstance(expression, str) else expression
for expression in expressions
)
super().__init__(name)
@property
def contains_expressions(self):
return bool(self.expressions)
def _get_condition_sql(self, model, schema_editor):
if self.condition is None:
return None
@ -136,39 +168,55 @@ class UniqueConstraint(BaseConstraint):
sql, params = where.as_sql(compiler, schema_editor.connection)
return sql % tuple(schema_editor.quote_value(p) for p in params)
def _get_index_expressions(self, model, schema_editor):
if not self.expressions:
return None
index_expressions = []
for expression in self.expressions:
index_expression = IndexExpression(expression)
index_expression.set_wrapper_classes(schema_editor.connection)
index_expressions.append(index_expression)
return ExpressionList(*index_expressions).resolve_expression(
Query(model, alias_cols=False),
)
def constraint_sql(self, model, schema_editor):
fields = [model._meta.get_field(field_name).column for field_name in self.fields]
include = [model._meta.get_field(field_name).column for field_name in self.include]
condition = self._get_condition_sql(model, schema_editor)
expressions = self._get_index_expressions(model, schema_editor)
return schema_editor._unique_sql(
model, fields, self.name, condition=condition,
deferrable=self.deferrable, include=include,
opclasses=self.opclasses,
opclasses=self.opclasses, expressions=expressions,
)
def create_sql(self, model, schema_editor):
fields = [model._meta.get_field(field_name).column for field_name in self.fields]
include = [model._meta.get_field(field_name).column for field_name in self.include]
condition = self._get_condition_sql(model, schema_editor)
expressions = self._get_index_expressions(model, schema_editor)
return schema_editor._create_unique_sql(
model, fields, self.name, condition=condition,
deferrable=self.deferrable, include=include,
opclasses=self.opclasses,
opclasses=self.opclasses, expressions=expressions,
)
def remove_sql(self, model, schema_editor):
condition = self._get_condition_sql(model, schema_editor)
include = [model._meta.get_field(field_name).column for field_name in self.include]
expressions = self._get_index_expressions(model, schema_editor)
return schema_editor._delete_unique_sql(
model, self.name, condition=condition, deferrable=self.deferrable,
include=include, opclasses=self.opclasses,
include=include, opclasses=self.opclasses, expressions=expressions,
)
def __repr__(self):
return '<%s: fields=%s name=%s%s%s%s%s>' % (
return '<%s:%s%s%s%s%s%s%s>' % (
self.__class__.__qualname__,
repr(self.fields),
repr(self.name),
'' if not self.fields else ' fields=%s' % repr(self.fields),
'' if not self.expressions else ' expressions=%s' % repr(self.expressions),
' name=%s' % repr(self.name),
'' if self.condition is None else ' condition=%s' % self.condition,
'' if self.deferrable is None else ' deferrable=%s' % self.deferrable,
'' if not self.include else ' include=%s' % repr(self.include),
@ -183,12 +231,14 @@ class UniqueConstraint(BaseConstraint):
self.condition == other.condition and
self.deferrable == other.deferrable and
self.include == other.include and
self.opclasses == other.opclasses
self.opclasses == other.opclasses and
self.expressions == other.expressions
)
return super().__eq__(other)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.fields:
kwargs['fields'] = self.fields
if self.condition:
kwargs['condition'] = self.condition
@ -198,4 +248,4 @@ class UniqueConstraint(BaseConstraint):
kwargs['include'] = self.include
if self.opclasses:
kwargs['opclasses'] = self.opclasses
return path, args, kwargs
return path, self.expressions, kwargs

View File

@ -391,6 +391,8 @@ Models
* **models.W042**: Auto-created primary key used when not defining a primary
key type, by default ``django.db.models.AutoField``.
* **models.W043**: ``<database>`` does not support indexes on expressions.
* **models.W044**: ``<database>`` does not support unique constraints on
expressions.
Security
--------

View File

@ -183,10 +183,10 @@ available from the ``django.contrib.postgres.indexes`` module.
.. class:: OpClass(expression, name)
An ``OpClass()`` expression represents the ``expression`` with a custom
`operator class`_ that can be used to define functional indexes. To use it,
you need to add ``'django.contrib.postgres'`` in your
:setting:`INSTALLED_APPS`. Set the ``name`` parameter to the name of the
`operator class`_.
`operator class`_ that can be used to define functional indexes or unique
constraints. To use it, you need to add ``'django.contrib.postgres'`` in
your :setting:`INSTALLED_APPS`. Set the ``name`` parameter to the name of
the `operator class`_.
For example::
@ -197,4 +197,18 @@ available from the ``django.contrib.postgres.indexes`` module.
creates an index on ``Lower('username')`` using ``varchar_pattern_ops``.
Another example::
UniqueConstraint(
OpClass(Upper('description'), name='text_pattern_ops'),
name='upper_description_unique',
)
creates a unique constraint on ``Upper('description')`` using
``text_pattern_ops``.
.. versionchanged:: 4.0
Support for functional unique constraints was added.
.. _operator class: https://www.postgresql.org/docs/current/indexes-opclass.html

View File

@ -69,10 +69,30 @@ constraint.
``UniqueConstraint``
====================
.. class:: UniqueConstraint(*, fields, name, condition=None, deferrable=None, include=None, opclasses=())
.. class:: UniqueConstraint(*expressions, fields=(), name=None, condition=None, deferrable=None, include=None, opclasses=())
Creates a unique constraint in the database.
``expressions``
---------------
.. attribute:: UniqueConstraint.expressions
.. versionadded:: 4.0
Positional argument ``*expressions`` allows creating functional unique
constraints on expressions and database functions.
For example::
UniqueConstraint(Lower('name').desc(), 'category', name='unique_lower_name_category')
creates a unique constraint on the lowercased value of the ``name`` field in
descending order and the ``category`` field in the default ascending order.
Functional unique constraints have the same database restrictions as
:attr:`Index.expressions`.
``fields``
----------

View File

@ -28,6 +28,36 @@ The Django 3.2.x series is the last to support Python 3.6 and 3.7.
What's new in Django 4.0
========================
Functional unique constraints
-----------------------------
The new :attr:`*expressions <django.db.models.UniqueConstraint.expressions>`
positional argument of
:class:`UniqueConstraint() <django.db.models.UniqueConstraint>` enables
creating functional unique constraints on expressions and database functions.
For example::
from django.db import models
from django.db.models import UniqueConstraint
from django.db.models.functions import Lower
class MyModel(models.Model):
first_name = models.CharField(max_length=255)
last_name = models.CharField(max_length=255)
class Meta:
indexes = [
UniqueConstraint(
Lower('first_name'),
Lower('last_name').desc(),
name='first_last_name_unique',
),
]
Functional unique constraints are added to models using the
:attr:`Meta.constraints <django.db.models.Options.constraints>` option.
Minor features
--------------

View File

@ -2,7 +2,9 @@ from unittest import mock
from django.core.exceptions import ValidationError
from django.db import IntegrityError, connection, models
from django.db.models import F
from django.db.models.constraints import BaseConstraint
from django.db.models.functions import Lower
from django.db.transaction import atomic
from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
@ -25,6 +27,10 @@ class BaseConstraintTests(SimpleTestCase):
with self.assertRaisesMessage(NotImplementedError, msg):
c.constraint_sql(None, None)
def test_contains_expressions(self):
c = BaseConstraint('name')
self.assertIs(c.contains_expressions, False)
def test_create_sql(self):
c = BaseConstraint('name')
msg = 'This method must be implemented by a subclass.'
@ -218,6 +224,25 @@ class UniqueConstraintTests(TestCase):
self.assertEqual(constraint_1, constraint_1)
self.assertNotEqual(constraint_1, constraint_2)
def test_eq_with_expressions(self):
constraint = models.UniqueConstraint(
Lower('title'),
F('author'),
name='book_func_uq',
)
same_constraint = models.UniqueConstraint(
Lower('title'),
'author',
name='book_func_uq',
)
another_constraint = models.UniqueConstraint(
Lower('title'),
name='book_func_uq',
)
self.assertEqual(constraint, same_constraint)
self.assertEqual(constraint, mock.ANY)
self.assertNotEqual(constraint, another_constraint)
def test_repr(self):
fields = ['foo', 'bar']
name = 'unique_fields'
@ -275,6 +300,18 @@ class UniqueConstraintTests(TestCase):
"opclasses=['text_pattern_ops', 'varchar_pattern_ops']>",
)
def test_repr_with_expressions(self):
constraint = models.UniqueConstraint(
Lower('title'),
F('author'),
name='book_func_uq',
)
self.assertEqual(
repr(constraint),
"<UniqueConstraint: expressions=(Lower(F(title)), F(author)) "
"name='book_func_uq'>",
)
def test_deconstruction(self):
fields = ['foo', 'bar']
name = 'unique_fields'
@ -339,6 +376,14 @@ class UniqueConstraintTests(TestCase):
'opclasses': opclasses,
})
def test_deconstruction_with_expressions(self):
name = 'unique_fields'
constraint = models.UniqueConstraint(Lower('title'), name=name)
path, args, kwargs = constraint.deconstruct()
self.assertEqual(path, 'django.db.models.UniqueConstraint')
self.assertEqual(args, (Lower('title'),))
self.assertEqual(kwargs, {'name': name})
def test_database_constraint(self):
with self.assertRaises(IntegrityError):
UniqueConstraintProduct.objects.create(name=self.p1.name, color=self.p1.color)
@ -434,6 +479,15 @@ class UniqueConstraintTests(TestCase):
deferrable=models.Deferrable.DEFERRED,
)
def test_deferrable_with_expressions(self):
message = 'UniqueConstraint with expressions cannot be deferred.'
with self.assertRaisesMessage(ValueError, message):
models.UniqueConstraint(
Lower('name'),
name='deferred_expression_unique',
deferrable=models.Deferrable.DEFERRED,
)
def test_invalid_defer_argument(self):
message = 'UniqueConstraint.deferrable must be a Deferrable instance.'
with self.assertRaisesMessage(ValueError, message):
@ -481,3 +535,33 @@ class UniqueConstraintTests(TestCase):
fields=['field'],
opclasses=['foo', 'bar'],
)
def test_requires_field_or_expression(self):
msg = (
'At least one field or expression is required to define a unique '
'constraint.'
)
with self.assertRaisesMessage(ValueError, msg):
models.UniqueConstraint(name='name')
def test_expressions_and_fields_mutually_exclusive(self):
msg = 'UniqueConstraint.fields and expressions are mutually exclusive.'
with self.assertRaisesMessage(ValueError, msg):
models.UniqueConstraint(Lower('field_1'), fields=['field_2'], name='name')
def test_expressions_with_opclasses(self):
msg = (
'UniqueConstraint.opclasses cannot be used with expressions. Use '
'django.contrib.postgres.indexes.OpClass() instead.'
)
with self.assertRaisesMessage(ValueError, msg):
models.UniqueConstraint(
Lower('field'),
name='test_func_opclass',
opclasses=['jsonb_path_ops'],
)
def test_requires_name(self):
msg = 'A unique constraint must be named.'
with self.assertRaisesMessage(ValueError, msg):
models.UniqueConstraint(fields=['field'])

View File

@ -2178,3 +2178,144 @@ class ConstraintsTests(TestCase):
]
self.assertEqual(Model.check(databases=self.databases), [])
def test_func_unique_constraint(self):
class Model(models.Model):
name = models.CharField(max_length=10)
class Meta:
constraints = [
models.UniqueConstraint(Lower('name'), name='lower_name_uq'),
]
warn = Warning(
'%s does not support unique constraints on expressions.'
% connection.display_name,
hint=(
"A constraint won't be created. Silence this warning if you "
"don't care about it."
),
obj=Model,
id='models.W044',
)
expected = [] if connection.features.supports_expression_indexes else [warn]
self.assertEqual(Model.check(databases=self.databases), expected)
def test_func_unique_constraint_required_db_features(self):
class Model(models.Model):
name = models.CharField(max_length=10)
class Meta:
constraints = [
models.UniqueConstraint(Lower('name'), name='lower_name_unq'),
]
required_db_features = {'supports_expression_indexes'}
self.assertEqual(Model.check(databases=self.databases), [])
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_expression_custom_lookup(self):
class Model(models.Model):
height = models.IntegerField()
weight = models.IntegerField()
class Meta:
constraints = [
models.UniqueConstraint(
models.F('height') / (models.F('weight__abs') + models.Value(5)),
name='name',
),
]
with register_lookup(models.IntegerField, Abs):
self.assertEqual(Model.check(databases=self.databases), [])
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_pointing_to_missing_field(self):
class Model(models.Model):
class Meta:
constraints = [
models.UniqueConstraint(Lower('missing_field').desc(), name='name'),
]
self.assertEqual(Model.check(databases=self.databases), [
Error(
"'constraints' refers to the nonexistent field "
"'missing_field'.",
obj=Model,
id='models.E012',
),
])
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_pointing_to_missing_field_nested(self):
class Model(models.Model):
class Meta:
constraints = [
models.UniqueConstraint(Abs(Round('missing_field')), name='name'),
]
self.assertEqual(Model.check(databases=self.databases), [
Error(
"'constraints' refers to the nonexistent field "
"'missing_field'.",
obj=Model,
id='models.E012',
),
])
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_pointing_to_m2m_field(self):
class Model(models.Model):
m2m = models.ManyToManyField('self')
class Meta:
constraints = [models.UniqueConstraint(Lower('m2m'), name='name')]
self.assertEqual(Model.check(databases=self.databases), [
Error(
"'constraints' refers to a ManyToManyField 'm2m', but "
"ManyToManyFields are not permitted in 'constraints'.",
obj=Model,
id='models.E013',
),
])
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_pointing_to_non_local_field(self):
class Foo(models.Model):
field1 = models.CharField(max_length=15)
class Bar(Foo):
class Meta:
constraints = [models.UniqueConstraint(Lower('field1'), name='name')]
self.assertEqual(Bar.check(databases=self.databases), [
Error(
"'constraints' refers to field 'field1' which is not local to "
"model 'Bar'.",
hint='This issue may be caused by multi-table inheritance.',
obj=Bar,
id='models.E016',
),
])
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_pointing_to_fk(self):
class Foo(models.Model):
id = models.CharField(primary_key=True, max_length=255)
class Bar(models.Model):
foo_1 = models.ForeignKey(Foo, models.CASCADE, related_name='bar_1')
foo_2 = models.ForeignKey(Foo, models.CASCADE, related_name='bar_2')
class Meta:
constraints = [
models.UniqueConstraint(
Lower('foo_1_id'),
Lower('foo_2'),
name='name',
),
]
self.assertEqual(Bar.check(databases=self.databases), [])

View File

@ -2562,6 +2562,99 @@ class OperationTests(OperationTestBase):
'name': 'covering_pink_constraint_rm',
})
def test_add_func_unique_constraint(self):
app_label = 'test_adfuncuc'
constraint_name = f'{app_label}_pony_abs_uq'
table_name = f'{app_label}_pony'
project_state = self.set_up_test_model(app_label)
constraint = models.UniqueConstraint(Abs('weight'), name=constraint_name)
operation = migrations.AddConstraint('Pony', constraint)
self.assertEqual(
operation.describe(),
'Create constraint test_adfuncuc_pony_abs_uq on model Pony',
)
self.assertEqual(
operation.migration_name_fragment,
'pony_test_adfuncuc_pony_abs_uq',
)
new_state = project_state.clone()
operation.state_forwards(app_label, new_state)
self.assertEqual(len(new_state.models[app_label, 'pony'].options['constraints']), 1)
self.assertIndexNameNotExists(table_name, constraint_name)
# Add constraint.
with connection.schema_editor() as editor:
operation.database_forwards(app_label, editor, project_state, new_state)
Pony = new_state.apps.get_model(app_label, 'Pony')
Pony.objects.create(weight=4.0)
if connection.features.supports_expression_indexes:
self.assertIndexNameExists(table_name, constraint_name)
with self.assertRaises(IntegrityError):
Pony.objects.create(weight=-4.0)
else:
self.assertIndexNameNotExists(table_name, constraint_name)
Pony.objects.create(weight=-4.0)
# Reversal.
with connection.schema_editor() as editor:
operation.database_backwards(app_label, editor, new_state, project_state)
self.assertIndexNameNotExists(table_name, constraint_name)
# Constraint doesn't work.
Pony.objects.create(weight=-4.0)
# Deconstruction.
definition = operation.deconstruct()
self.assertEqual(definition[0], 'AddConstraint')
self.assertEqual(definition[1], [])
self.assertEqual(
definition[2],
{'model_name': 'Pony', 'constraint': constraint},
)
def test_remove_func_unique_constraint(self):
app_label = 'test_rmfuncuc'
constraint_name = f'{app_label}_pony_abs_uq'
table_name = f'{app_label}_pony'
project_state = self.set_up_test_model(app_label, constraints=[
models.UniqueConstraint(Abs('weight'), name=constraint_name),
])
self.assertTableExists(table_name)
if connection.features.supports_expression_indexes:
self.assertIndexNameExists(table_name, constraint_name)
operation = migrations.RemoveConstraint('Pony', constraint_name)
self.assertEqual(
operation.describe(),
'Remove constraint test_rmfuncuc_pony_abs_uq from model Pony',
)
self.assertEqual(
operation.migration_name_fragment,
'remove_pony_test_rmfuncuc_pony_abs_uq',
)
new_state = project_state.clone()
operation.state_forwards(app_label, new_state)
self.assertEqual(len(new_state.models[app_label, 'pony'].options['constraints']), 0)
Pony = new_state.apps.get_model(app_label, 'Pony')
self.assertEqual(len(Pony._meta.constraints), 0)
# Remove constraint.
with connection.schema_editor() as editor:
operation.database_forwards(app_label, editor, project_state, new_state)
self.assertIndexNameNotExists(table_name, constraint_name)
# Constraint doesn't work.
Pony.objects.create(pink=1, weight=4.0)
Pony.objects.create(pink=1, weight=-4.0).delete()
# Reversal.
with connection.schema_editor() as editor:
operation.database_backwards(app_label, editor, new_state, project_state)
if connection.features.supports_expression_indexes:
self.assertIndexNameExists(table_name, constraint_name)
with self.assertRaises(IntegrityError):
Pony.objects.create(weight=-4.0)
else:
self.assertIndexNameNotExists(table_name, constraint_name)
Pony.objects.create(weight=-4.0)
# Deconstruction.
definition = operation.deconstruct()
self.assertEqual(definition[0], 'RemoveConstraint')
self.assertEqual(definition[1], [])
self.assertEqual(definition[2], {'model_name': 'Pony', 'name': constraint_name})
def test_alter_model_options(self):
"""
Tests the AlterModelOptions operation.

View File

@ -1,6 +1,7 @@
import datetime
from unittest import mock
from django.contrib.postgres.indexes import OpClass
from django.db import (
IntegrityError, NotSupportedError, connection, transaction,
)
@ -8,8 +9,8 @@ from django.db.models import (
CheckConstraint, Deferrable, F, Func, IntegerField, Q, UniqueConstraint,
)
from django.db.models.fields.json import KeyTextTransform
from django.db.models.functions import Cast, Left
from django.test import skipUnlessDBFeature
from django.db.models.functions import Cast, Left, Lower
from django.test import modify_settings, skipUnlessDBFeature
from django.utils import timezone
from . import PostgreSQLTestCase
@ -26,6 +27,7 @@ except ImportError:
pass
@modify_settings(INSTALLED_APPS={'append': 'django.contrib.postgres'})
class SchemaTests(PostgreSQLTestCase):
get_opclass_query = '''
SELECT opcname, c.relname FROM pg_opclass AS oc
@ -166,6 +168,33 @@ class SchemaTests(PostgreSQLTestCase):
[('varchar_pattern_ops', constraint.name)],
)
@skipUnlessDBFeature('supports_expression_indexes')
def test_opclass_func(self):
constraint = UniqueConstraint(
OpClass(Lower('scene'), name='text_pattern_ops'),
name='test_opclass_func',
)
with connection.schema_editor() as editor:
editor.add_constraint(Scene, constraint)
constraints = self.get_constraints(Scene._meta.db_table)
self.assertIs(constraints[constraint.name]['unique'], True)
self.assertIn(constraint.name, constraints)
with editor.connection.cursor() as cursor:
cursor.execute(self.get_opclass_query, [constraint.name])
self.assertEqual(
cursor.fetchall(),
[('text_pattern_ops', constraint.name)],
)
Scene.objects.create(scene='Scene 10', setting='The dark forest of Ewing')
with self.assertRaises(IntegrityError), transaction.atomic():
Scene.objects.create(scene='ScEnE 10', setting="Sir Bedemir's Castle")
Scene.objects.create(scene='Scene 5', setting="Sir Bedemir's Castle")
# Drop the constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(Scene, constraint)
self.assertNotIn(constraint.name, self.get_constraints(Scene._meta.db_table))
Scene.objects.create(scene='ScEnE 10', setting="Sir Bedemir's Castle")
class ExclusionConstraintTests(PostgreSQLTestCase):
def get_constraints(self, table):

View File

@ -2189,6 +2189,246 @@ class SchemaTests(TransactionTestCase):
AuthorWithUniqueNameAndBirthday._meta.constraints = []
editor.remove_constraint(AuthorWithUniqueNameAndBirthday, constraint)
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
constraint = UniqueConstraint(Upper('name').desc(), name='func_upper_uq')
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(Author, constraint)
sql = constraint.create_sql(Author, editor)
table = Author._meta.db_table
constraints = self.get_constraints(table)
if connection.features.supports_index_column_ordering:
self.assertIndexOrder(table, constraint.name, ['DESC'])
self.assertIn(constraint.name, constraints)
self.assertIs(constraints[constraint.name]['unique'], True)
# SQL contains a database function.
self.assertIs(sql.references_column(table, 'name'), True)
self.assertIn('UPPER(%s)' % editor.quote_name('name'), str(sql))
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(Author, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipUnlessDBFeature('supports_expression_indexes')
def test_composite_func_unique_constraint(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
editor.create_model(BookWithSlug)
constraint = UniqueConstraint(
Upper('title'),
Lower('slug'),
name='func_upper_lower_unq',
)
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(BookWithSlug, constraint)
sql = constraint.create_sql(BookWithSlug, editor)
table = BookWithSlug._meta.db_table
constraints = self.get_constraints(table)
self.assertIn(constraint.name, constraints)
self.assertIs(constraints[constraint.name]['unique'], True)
# SQL contains database functions.
self.assertIs(sql.references_column(table, 'title'), True)
self.assertIs(sql.references_column(table, 'slug'), True)
sql = str(sql)
self.assertIn('UPPER(%s)' % editor.quote_name('title'), sql)
self.assertIn('LOWER(%s)' % editor.quote_name('slug'), sql)
self.assertLess(sql.index('UPPER'), sql.index('LOWER'))
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(BookWithSlug, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipUnlessDBFeature('supports_expression_indexes')
def test_unique_constraint_field_and_expression(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
constraint = UniqueConstraint(
F('height').desc(),
'uuid',
Lower('name').asc(),
name='func_f_lower_field_unq',
)
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(Author, constraint)
sql = constraint.create_sql(Author, editor)
table = Author._meta.db_table
if connection.features.supports_index_column_ordering:
self.assertIndexOrder(table, constraint.name, ['DESC', 'ASC', 'ASC'])
constraints = self.get_constraints(table)
self.assertIs(constraints[constraint.name]['unique'], True)
self.assertEqual(len(constraints[constraint.name]['columns']), 3)
self.assertEqual(constraints[constraint.name]['columns'][1], 'uuid')
# SQL contains database functions and columns.
self.assertIs(sql.references_column(table, 'height'), True)
self.assertIs(sql.references_column(table, 'name'), True)
self.assertIs(sql.references_column(table, 'uuid'), True)
self.assertIn('LOWER(%s)' % editor.quote_name('name'), str(sql))
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(Author, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipUnlessDBFeature('supports_expression_indexes', 'supports_partial_indexes')
def test_func_unique_constraint_partial(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
constraint = UniqueConstraint(
Upper('name'),
name='func_upper_cond_weight_uq',
condition=Q(weight__isnull=False),
)
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(Author, constraint)
sql = constraint.create_sql(Author, editor)
table = Author._meta.db_table
constraints = self.get_constraints(table)
self.assertIn(constraint.name, constraints)
self.assertIs(constraints[constraint.name]['unique'], True)
self.assertIs(sql.references_column(table, 'name'), True)
self.assertIn('UPPER(%s)' % editor.quote_name('name'), str(sql))
self.assertIn(
'WHERE %s IS NOT NULL' % editor.quote_name('weight'),
str(sql),
)
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(Author, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipUnlessDBFeature('supports_expression_indexes', 'supports_covering_indexes')
def test_func_unique_constraint_covering(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
constraint = UniqueConstraint(
Upper('name'),
name='func_upper_covering_uq',
include=['weight', 'height'],
)
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(Author, constraint)
sql = constraint.create_sql(Author, editor)
table = Author._meta.db_table
constraints = self.get_constraints(table)
self.assertIn(constraint.name, constraints)
self.assertIs(constraints[constraint.name]['unique'], True)
self.assertEqual(
constraints[constraint.name]['columns'],
[None, 'weight', 'height'],
)
self.assertIs(sql.references_column(table, 'name'), True)
self.assertIs(sql.references_column(table, 'weight'), True)
self.assertIs(sql.references_column(table, 'height'), True)
self.assertIn('UPPER(%s)' % editor.quote_name('name'), str(sql))
self.assertIn(
'INCLUDE (%s, %s)' % (
editor.quote_name('weight'),
editor.quote_name('height'),
),
str(sql),
)
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(Author, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_lookups(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
with register_lookup(CharField, Lower), register_lookup(IntegerField, Abs):
constraint = UniqueConstraint(
F('name__lower'),
F('weight__abs'),
name='func_lower_abs_lookup_uq',
)
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(Author, constraint)
sql = constraint.create_sql(Author, editor)
table = Author._meta.db_table
constraints = self.get_constraints(table)
self.assertIn(constraint.name, constraints)
self.assertIs(constraints[constraint.name]['unique'], True)
# SQL contains columns.
self.assertIs(sql.references_column(table, 'name'), True)
self.assertIs(sql.references_column(table, 'weight'), True)
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(Author, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_collate(self):
collation = connection.features.test_collations.get('non_default')
if not collation:
self.skipTest(
'This backend does not support case-insensitive collations.'
)
with connection.schema_editor() as editor:
editor.create_model(Author)
editor.create_model(BookWithSlug)
constraint = UniqueConstraint(
Collate(F('title'), collation=collation).desc(),
Collate('slug', collation=collation),
name='func_collate_uq',
)
# Add constraint.
with connection.schema_editor() as editor:
editor.add_constraint(BookWithSlug, constraint)
sql = constraint.create_sql(BookWithSlug, editor)
table = BookWithSlug._meta.db_table
constraints = self.get_constraints(table)
self.assertIn(constraint.name, constraints)
self.assertIs(constraints[constraint.name]['unique'], True)
if connection.features.supports_index_column_ordering:
self.assertIndexOrder(table, constraint.name, ['DESC', 'ASC'])
# SQL contains columns and a collation.
self.assertIs(sql.references_column(table, 'title'), True)
self.assertIs(sql.references_column(table, 'slug'), True)
self.assertIn('COLLATE %s' % editor.quote_name(collation), str(sql))
# Remove constraint.
with connection.schema_editor() as editor:
editor.remove_constraint(BookWithSlug, constraint)
self.assertNotIn(constraint.name, self.get_constraints(table))
@skipIfDBFeature('supports_expression_indexes')
def test_func_unique_constraint_unsupported(self):
# UniqueConstraint is ignored on databases that don't support indexes on
# expressions.
with connection.schema_editor() as editor:
editor.create_model(Author)
constraint = UniqueConstraint(F('name'), name='func_name_uq')
with connection.schema_editor() as editor, self.assertNumQueries(0):
self.assertIsNone(editor.add_constraint(Author, constraint))
self.assertIsNone(editor.remove_constraint(Author, constraint))
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_nonexistent_field(self):
constraint = UniqueConstraint(Lower('nonexistent'), name='func_nonexistent_uq')
msg = (
"Cannot resolve keyword 'nonexistent' into field. Choices are: "
"height, id, name, uuid, weight"
)
with self.assertRaisesMessage(FieldError, msg):
with connection.schema_editor() as editor:
editor.add_constraint(Author, constraint)
@skipUnlessDBFeature('supports_expression_indexes')
def test_func_unique_constraint_nondeterministic(self):
with connection.schema_editor() as editor:
editor.create_model(Author)
constraint = UniqueConstraint(Random(), name='func_random_uq')
with connection.schema_editor() as editor:
with self.assertRaises(DatabaseError):
editor.add_constraint(Author, constraint)
def test_index_together(self):
"""
Tests removing and adding index_together constraints on a model.