on OSX, MemoryErrors abound and just plain broken
unicode support. [ticket:2273]
+ - The behavior of =/!= when comparing a scalar select
+ to a value will no longer produce IN/NOT IN as of 0.8;
+ this behavior is a little too heavy handed (use in_() if
+ you want to emit IN) and now emits a deprecation warning.
+ To get the 0.8 behavior immediately and remove the warning,
+ a compiler recipe is given at
+ http://www.sqlalchemy.org/docs/07/dialects/mssql.html#scalar-select-comparisons
+ to override the behavior of visit_binary().
+ [ticket:2277]
+
- "0" is accepted as an argument for limit() which
will produce "TOP 0". [ticket:2222]
Background on SQL Server snapshot isolation is available at
http://msdn.microsoft.com/en-us/library/ms175095.aspx.
-
+
+Scalar Select Comparisons
+-------------------------
+
+The MSSQL dialect contains a legacy behavior whereby comparing
+a scalar select to a value using the ``=`` or ``!=`` operator
+will resolve to IN or NOT IN, respectively. This behavior is
+deprecated and will be removed in 0.8 - the ``s.in_()``/``~s.in_()`` operators
+should be used when IN/NOT IN are desired.
+
+For the time being, the existing behavior prevents a comparison
+between scalar select and another value that actually wants to use ``=``.
+To remove this behavior in a forwards-compatible way, apply this
+compilation rule by placing the following code at the module import
+level::
+
+ from sqlalchemy.ext.compiler import compiles
+ from sqlalchemy.sql.expression import _BinaryExpression
+ from sqlalchemy.sql.compiler import SQLCompiler
+
+ @compiles(_BinaryExpression, 'mssql')
+ def override_legacy_binary(element, compiler, **kw):
+ return SQLCompiler.visit_binary(compiler, element, **kw)
+
Known Issues
------------
)
):
op = binary.operator == operator.eq and "IN" or "NOT IN"
+ util.warn_deprecated("Comparing a scalar select using ``=``/``!=`` will "
+ "no longer produce IN/NOT IN in 0.8. To remove this "
+ "behavior immediately, use the recipe at "
+ "http://www.sqlalchemy.org/docs/07/dialects/mssql.html#scalar-select-comparisons")
return self.process(
expression._BinaryExpression(binary.left,
binary.right, op),
]:
self.assert_compile(expr, compile, dialect=mxodbc_dialect)
+ @testing.uses_deprecated
def test_in_with_subqueries(self):
"""Test that when using subqueries in a binary expression
the == and != are changed to IN and NOT IN respectively.
'DELETE FROM paj.test WHERE paj.test.id = '
':id_1')
s = select([tbl.c.id]).where(tbl.c.id == 1)
- self.assert_compile(tbl.delete().where(tbl.c.id == s),
+ self.assert_compile(tbl.delete().where(tbl.c.id.in_(s)),
'DELETE FROM paj.test WHERE paj.test.id IN '
'(SELECT test_1.id FROM paj.test AS test_1 '
'WHERE test_1.id = :id_1)')
'DELETE FROM banana.paj.test WHERE '
'banana.paj.test.id = :id_1')
s = select([tbl.c.id]).where(tbl.c.id == 1)
- self.assert_compile(tbl.delete().where(tbl.c.id == s),
+ self.assert_compile(tbl.delete().where(tbl.c.id.in_(s)),
'DELETE FROM banana.paj.test WHERE '
'banana.paj.test.id IN (SELECT test_1.id '
'FROM banana.paj.test AS test_1 WHERE '
'DELETE FROM [banana split].paj.test WHERE '
'[banana split].paj.test.id = :id_1')
s = select([tbl.c.id]).where(tbl.c.id == 1)
- self.assert_compile(tbl.delete().where(tbl.c.id == s),
+ self.assert_compile(tbl.delete().where(tbl.c.id.in_(s)),
'DELETE FROM [banana split].paj.test WHERE '
'[banana split].paj.test.id IN (SELECT '
'test_1.id FROM [banana split].paj.test AS '
'space].test WHERE [banana split].[paj '
'with a space].test.id = :id_1')
s = select([tbl.c.id]).where(tbl.c.id == 1)
- self.assert_compile(tbl.delete().where(tbl.c.id == s),
+ self.assert_compile(tbl.delete().where(tbl.c.id.in_(s)),
'DELETE FROM [banana split].[paj with a '
'space].test WHERE [banana split].[paj '
'with a space].test.id IN (SELECT '
# the subquery and usually results in recursion overflow errors within the adaption.
subq = sess.query(engineers.c.person_id).filter(Engineer.primary_language=='java').statement.as_scalar()
- eq_(sess.query(Person).filter(Person.person_id==subq).one(), e1)
+ eq_(sess.query(Person).filter(Person.person_id.in_(subq)).one(), e1)
def test_mixed_entities(self):
sess = create_session()
from test.lib.schema import Table, Column
from sqlalchemy.orm import mapper, relationship, create_session, \
lazyload, aliased, column_property
+from sqlalchemy.sql import operators
from test.lib.testing import eq_, assert_raises, \
assert_raises_message
from test.lib.assertsql import CompiledSQL
stuff_view = select([salias.c.id]).where(salias.c.user_id==users.c.id).\
correlate(users).order_by(salias.c.date.desc()).limit(1)
+ operator = operators.in_op
if labeled == 'label':
stuff_view = stuff_view.label('foo')
+ operator = operators.eq
elif labeled == 'scalar':
stuff_view = stuff_view.as_scalar()
if ondate:
mapper(User, users, properties={
- 'stuff':relationship(Stuff, primaryjoin=and_(users.c.id==stuff.c.user_id, stuff.c.date==stuff_view))
+ 'stuff':relationship(Stuff, primaryjoin=and_(users.c.id==stuff.c.user_id, operator(stuff.c.date, stuff_view)))
})
else:
mapper(User, users, properties={
- 'stuff':relationship(Stuff, primaryjoin=and_(users.c.id==stuff.c.user_id, stuff.c.id==stuff_view))
+ 'stuff':relationship(Stuff, primaryjoin=and_(users.c.id==stuff.c.user_id, operator(stuff.c.id, stuff_view)))
})
sess = create_session()
'IN (SELECT users.id FROM users WHERE '
'users.id = :id_1)')
-
+ @testing.fails_on('mssql', "mssql doesn't allow col = <subquery>, sqla deprecated workaround")
def test_param_transfer(self):
User = self.classes.User
projects / thirdparty / sqlalchemy / sqlalchemy.git / commitdiff
