Files
sqlalchemy/test/sql/test_identity_column.py
T
Federico Caselli 3ebc3710a7 `Identity implies nullable=False`.
Altered the behavior of the :class:`_schema.Identity` construct such that
when applied to a :class:`_schema.Column`, it will automatically imply that
the value of :paramref:`_sql.Column.nullable` should default to ``False``,
in a similar manner as when the :paramref:`_sql.Column.primary_key`
parameter is set to ``True``.   This matches the default behavior of all
supporting databases where ``IDENTITY`` implies ``NOT NULL``.  The
PostgreSQL backend is the only one that supports adding ``NULL`` to an
``IDENTITY`` column, which is here supported by passing a ``True`` value
for the :paramref:`_sql.Column.nullable` parameter at the same time.

Fixes: #5775
Change-Id: I0516d506ff327cff35cda605e8897a27440e0373
2021-01-16 18:39:11 -05:00

284 lines
8.6 KiB
Python

from sqlalchemy import Column
from sqlalchemy import Identity
from sqlalchemy import Integer
from sqlalchemy import MetaData
from sqlalchemy import Sequence
from sqlalchemy import Table
from sqlalchemy import testing
from sqlalchemy.exc import ArgumentError
from sqlalchemy.schema import CreateTable
from sqlalchemy.testing import assert_raises_message
from sqlalchemy.testing import fixtures
from sqlalchemy.testing import is_
from sqlalchemy.testing import is_not_
class _IdentityDDLFixture(testing.AssertsCompiledSQL):
__backend__ = True
@testing.combinations(
(dict(always=True), "ALWAYS AS IDENTITY"),
(
dict(always=False, start=5),
"BY DEFAULT AS IDENTITY (START WITH 5)",
),
(
dict(always=True, increment=2),
"ALWAYS AS IDENTITY (INCREMENT BY 2)",
),
(
dict(increment=2, start=5),
"BY DEFAULT AS IDENTITY (INCREMENT BY 2 START WITH 5)",
),
(
dict(always=True, increment=2, start=0, minvalue=0),
"ALWAYS AS IDENTITY (INCREMENT BY 2 START WITH 0 MINVALUE 0)",
),
(
dict(always=False, increment=2, start=1, maxvalue=5),
"BY DEFAULT AS IDENTITY (INCREMENT BY 2 START WITH 1 MAXVALUE 5)",
),
(
dict(always=True, increment=2, start=1, nomaxvalue=True),
"ALWAYS AS IDENTITY (INCREMENT BY 2 START WITH 1 NO MAXVALUE)",
),
(
dict(always=False, increment=2, start=0, nominvalue=True),
"BY DEFAULT AS IDENTITY "
"(INCREMENT BY 2 START WITH 0 NO MINVALUE)",
),
(
dict(always=True, start=1, maxvalue=10, cycle=True),
"ALWAYS AS IDENTITY (START WITH 1 MAXVALUE 10 CYCLE)",
),
(
dict(always=False, cache=1000, order=True),
"BY DEFAULT AS IDENTITY (CACHE 1000 ORDER)",
),
(dict(order=True, cycle=True), "BY DEFAULT AS IDENTITY (ORDER CYCLE)"),
(
dict(order=False, cycle=False),
"BY DEFAULT AS IDENTITY (NO ORDER NO CYCLE)",
),
)
def test_create_ddl(self, identity_args, text):
if getattr(self, "__dialect__", None) != "default" and testing.against(
"oracle"
):
text = text.replace("NO MINVALUE", "NOMINVALUE")
text = text.replace("NO MAXVALUE", "NOMAXVALUE")
text = text.replace("NO CYCLE", "NOCYCLE")
text = text.replace("NO ORDER", "NOORDER")
t = Table(
"foo_table",
MetaData(),
Column("foo", Integer(), Identity(**identity_args)),
)
self.assert_compile(
CreateTable(t),
"CREATE TABLE foo_table (foo INTEGER GENERATED %s)" % text,
)
t2 = t.to_metadata(MetaData())
self.assert_compile(
CreateTable(t2),
"CREATE TABLE foo_table (foo INTEGER GENERATED %s)" % text,
)
def test_other_options(self):
t = Table(
"foo_table",
MetaData(),
Column(
"foo",
Integer(),
Identity(always=True, start=3),
nullable=False,
unique=True,
),
)
self.assert_compile(
CreateTable(t),
"CREATE TABLE foo_table ("
"foo INTEGER GENERATED ALWAYS AS IDENTITY (START "
"WITH 3), UNIQUE (foo))",
)
def test_autoincrement_true(self):
t = Table(
"foo_table",
MetaData(),
Column(
"foo",
Integer(),
Identity(always=True, start=3),
primary_key=True,
autoincrement=True,
),
)
self.assert_compile(
CreateTable(t),
"CREATE TABLE foo_table ("
"foo INTEGER GENERATED ALWAYS AS IDENTITY (START WITH 3)"
", PRIMARY KEY (foo))",
)
def test_nullable_kwarg(self):
t = Table(
"t",
MetaData(),
Column("a", Integer(), Identity(), nullable=False),
Column("b", Integer(), Identity(), nullable=True),
Column("c", Integer(), Identity()),
)
is_(t.c.a.nullable, False)
is_(t.c.b.nullable, True)
is_(t.c.c.nullable, False)
nullable = ""
if getattr(self, "__dialect__", None) != "default" and testing.against(
"postgresql"
):
nullable = " NULL"
self.assert_compile(
CreateTable(t),
(
"CREATE TABLE t ("
"a INTEGER GENERATED BY DEFAULT AS IDENTITY, "
"b INTEGER GENERATED BY DEFAULT AS IDENTITY%s, "
"c INTEGER GENERATED BY DEFAULT AS IDENTITY"
")"
)
% nullable,
)
class IdentityDDL(_IdentityDDLFixture, fixtures.TestBase):
# this uses the connection dialect
__requires__ = ("identity_columns_standard",)
def test_on_null(self):
t = Table(
"foo_table",
MetaData(),
Column(
"foo",
Integer(),
Identity(always=False, on_null=True, start=42, order=True),
),
)
text = " ON NULL" if testing.against("oracle") else ""
self.assert_compile(
CreateTable(t),
(
"CREATE TABLE foo_table (foo INTEGER GENERATED BY DEFAULT"
+ text
+ " AS IDENTITY (START WITH 42 ORDER))"
),
)
class DefaultDialectIdentityDDL(_IdentityDDLFixture, fixtures.TestBase):
# this uses the default dialect
__dialect__ = "default"
class NotSupportingIdentityDDL(testing.AssertsCompiledSQL, fixtures.TestBase):
# a dialect that doesn't render IDENTITY
__dialect__ = "sqlite"
@testing.skip_if(testing.requires.identity_columns)
def test_identity_is_ignored(self):
t = Table(
"foo_table",
MetaData(),
Column("foo", Integer(), Identity("always", start=3)),
)
self.assert_compile(
CreateTable(t), "CREATE TABLE foo_table (foo INTEGER NOT NULL)"
)
class IdentityTest(fixtures.TestBase):
def test_server_default_onupdate(self):
text = (
"A column with an Identity object cannot specify a "
"server_default or a server_onupdate argument"
)
def fn(**kwargs):
Table(
"t",
MetaData(),
Column("y", Integer, Identity(), **kwargs),
)
assert_raises_message(ArgumentError, text, fn, server_default="42")
assert_raises_message(ArgumentError, text, fn, server_onupdate="42")
def test_to_metadata(self):
identity1 = Identity("by default", on_null=True, start=123)
m = MetaData()
t = Table(
"t", m, Column("x", Integer), Column("y", Integer, identity1)
)
is_(identity1.column, t.c.y)
# is_(t.c.y.server_onupdate, identity1)
is_(t.c.y.server_default, identity1)
m2 = MetaData()
t2 = t.to_metadata(m2)
identity2 = t2.c.y.server_default
is_not_(identity1, identity2)
is_(identity1.column, t.c.y)
# is_(t.c.y.server_onupdate, identity1)
is_(t.c.y.server_default, identity1)
is_(identity2.column, t2.c.y)
# is_(t2.c.y.server_onupdate, identity2)
is_(t2.c.y.server_default, identity2)
def test_autoincrement_column(self):
t = Table(
"t",
MetaData(),
Column("y", Integer, Identity(), primary_key=True),
)
assert t._autoincrement_column is t.c.y
t2 = Table("t2", MetaData(), Column("y", Integer, Identity()))
assert t2._autoincrement_column is None
def test_identity_and_sequence(self):
def go():
return Table(
"foo_table",
MetaData(),
Column("foo", Integer(), Identity(), Sequence("foo_seq")),
)
assert_raises_message(
ArgumentError,
"An column cannot specify both Identity and Sequence.",
go,
)
def test_identity_autoincrement_false(self):
def go():
return Table(
"foo_table",
MetaData(),
Column("foo", Integer(), Identity(), autoincrement=False),
)
assert_raises_message(
ArgumentError,
"A column with an Identity object cannot specify "
"autoincrement=False",
go,
)