[sqlalchemy] Re: Polymorphic mappers on boolean types
Yeah once I'd worked it out I converted the field over to being an
int field, just didn't see this one coming :-) Maybe something worth
adding into the doco if it's going to stick around ?
On Monday 07 January 2008 02:03:19 Michael Bayer wrote:
yeah thats line 1303 of mapper.py. i think i might have made that
change right in 0.4.2 thinking, nobody would use a boolean False as
a discriminatorany chance you can go with some plain int or
string for that ?
On Jan 5, 2008, at 11:47 PM, Dave Harrison wrote:
Hey all,
More fun with inheritance and mappers. In the following situation
where the polymorphic type is a Boolean, the mapper for the object
that matches on False incorrectly returns the parent object.
Cheers
Dave
--
-- testapi.py
--
from sqlalchemy import *
from sqlalchemy.orm import *
session = scoped_session(
sessionmaker(autoflush=False, transactional=True)
)
mapper = session.mapper
metadata = MetaData()
ANIMAL_TYPE_DOG = True
ANIMAL_TYPE_CAT = False
VET_TYPE_CITY = 1
VET_TYPE_COUNTRY = 2
animalTable = Table(
'animal',
metadata,
Column('id', Integer, primary_key=True),
Column('type', Boolean, nullable=False),
Column('name', String(100), nullable=False),
Column('vet_id', Integer, ForeignKey('vet.id')),
)
vetTable = Table(
'vet',
metadata,
Column('id', Integer, primary_key=True),
Column('address', String(100), nullable=False),
Column('kennel', Boolean, nullable=False),
)
class _Animal(object):
pass
class Cat(_Animal):
pass
class Dog(_Animal):
pass
class Vet(object):
pass
vetMapper = mapper(
Vet,
vetTable,
properties = {
animals: relation(
_Animal,
backref=backref(vet, uselist=False),
cascade=all, delete-orphan
),
}
)
animalMapper = mapper(
_Animal,
animalTable,
polymorphic_on=animalTable.c.type,
)
mapper(
Dog,
inherits=animalMapper,
polymorphic_identity=ANIMAL_TYPE_DOG,
)
mapper(
Cat,
inherits=animalMapper,
polymorphic_identity=ANIMAL_TYPE_CAT,
)
def connect(uri):
engine = create_engine(uri, strategy=threadlocal)
metadata.bind = engine
return engine
def create():
metadata.create_all()
def drop():
metadata.drop_all()
--
-- test.py
--
import sys
import testapi as db
DB = sqlite:///memory
db.connect(DB)
db.create()
v = db.Vet()
v.address = 12 Foo St
v.kennel = True
c1 = db.Cat()
c1.name = muffin
c2 = db.Cat()
c2.name = bagel
d1 = db.Dog()
d1.name = rex
d2 = db.Dog()
d2.name = bill
db.session.flush()
db.session.clear()
for d in db.Query(db.Dog).all():
v.animals.append(d)
for c in db.Query(db.Cat).all():
v.animals.append(c)
db.session.flush()
db.session.clear()
v = db.Query(db.Vet).first()
for a in v.animals:
print a
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[sqlalchemy] Re: Emptying out the session of new objects
On Sunday 06 January 2008 05:30:04 Michael Bayer wrote: On Jan 4, 2008, at 9:46 PM, Dave Harrison wrote: Hey Mike, Below is a minimal test case that always produces the below failure for me under 0.4.2 but not under 0.4.1, OK, its actually something that was buggy in 0.4.1 but didnt produce a symptom, give r4003 a try which fixes this issue...0.4.2a is today Hi Mike, That seems to have solved it for me. Thanks for the quick turn around, SQLAlchemy and the team continue to amaze ! :-) Cheers Dave --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups sqlalchemy group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Polymorphic mappers on boolean types
Hey all,
More fun with inheritance and mappers. In the following situation
where the polymorphic type is a Boolean, the mapper for the object
that matches on False incorrectly returns the parent object.
Cheers
Dave
--
-- testapi.py
--
from sqlalchemy import *
from sqlalchemy.orm import *
session = scoped_session(
sessionmaker(autoflush=False, transactional=True)
)
mapper = session.mapper
metadata = MetaData()
ANIMAL_TYPE_DOG = True
ANIMAL_TYPE_CAT = False
VET_TYPE_CITY = 1
VET_TYPE_COUNTRY = 2
animalTable = Table(
'animal',
metadata,
Column('id', Integer, primary_key=True),
Column('type', Boolean, nullable=False),
Column('name', String(100), nullable=False),
Column('vet_id', Integer, ForeignKey('vet.id')),
)
vetTable = Table(
'vet',
metadata,
Column('id', Integer, primary_key=True),
Column('address', String(100), nullable=False),
Column('kennel', Boolean, nullable=False),
)
class _Animal(object):
pass
class Cat(_Animal):
pass
class Dog(_Animal):
pass
class Vet(object):
pass
vetMapper = mapper(
Vet,
vetTable,
properties = {
animals: relation(
_Animal,
backref=backref(vet, uselist=False),
cascade=all, delete-orphan
),
}
)
animalMapper = mapper(
_Animal,
animalTable,
polymorphic_on=animalTable.c.type,
)
mapper(
Dog,
inherits=animalMapper,
polymorphic_identity=ANIMAL_TYPE_DOG,
)
mapper(
Cat,
inherits=animalMapper,
polymorphic_identity=ANIMAL_TYPE_CAT,
)
def connect(uri):
engine = create_engine(uri, strategy=threadlocal)
metadata.bind = engine
return engine
def create():
metadata.create_all()
def drop():
metadata.drop_all()
--
-- test.py
--
import sys
import testapi as db
DB = sqlite:///memory
db.connect(DB)
db.create()
v = db.Vet()
v.address = 12 Foo St
v.kennel = True
c1 = db.Cat()
c1.name = muffin
c2 = db.Cat()
c2.name = bagel
d1 = db.Dog()
d1.name = rex
d2 = db.Dog()
d2.name = bill
db.session.flush()
db.session.clear()
for d in db.Query(db.Dog).all():
v.animals.append(d)
for c in db.Query(db.Cat).all():
v.animals.append(c)
db.session.flush()
db.session.clear()
v = db.Query(db.Vet).first()
for a in v.animals:
print a
--~--~-~--~~~---~--~~
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[sqlalchemy] Emptying out the session of new objects
Hey all, I'm unit testing my DB api's, and I've found that if I don't explicitly expunge my objects from the session at the end of each test, I get objects left over in the session when the next test runs. Is there an easy way of flushing all objects that are categorised as new in the session ?? Cheers Dave --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups sqlalchemy group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Emptying out the session of new objects
On Friday 04 January 2008 23:32:21 Alexandre da Silva wrote: Is there an easy way of flushing all objects that are categorised as new in the session ?? I think you can use session.clear(), it will remove objects from session, and persistent objects will stay on database. Att Alexandre I had been using session.clear up until now, but as of 0.4.2 I've found that I get this error for alot of my tests, object has no attribute '_sa_session_id' As background, the tests I have use a sqlite memory database, and on setUp do a meta.create_all and on tearDown do a meta.drop_all I've assumed that this error is due to me leaving objects around in the session, so my current theory is that I need to manually expunge the objects I create at the end of the test. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups sqlalchemy group. To post to this group, send email to sqlalchemy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sqlalchemy?hl=en -~--~~~~--~~--~--~---
[sqlalchemy] Re: Emptying out the session of new objects
On Saturday 05 January 2008 03:08:54 Michael Bayer wrote:
On Jan 4, 2008, at 7:44 AM, Dave Harrison wrote:
On Friday 04 January 2008 23:32:21 Alexandre da Silva wrote:
Is there an easy way of flushing all objects that are categorised
as new in the session ??
I think you can use session.clear(), it will remove objects from
session, and persistent objects will stay on database.
Att
Alexandre
I had been using session.clear up until now, but as of 0.4.2 I've
found that I get this error for alot of my tests,
object has no attribute '_sa_session_id'
thats a bug. can you please provide a reproducing test case ?
this is actually pretty serious and a new release will be available
the moment we fix this.
Hey Mike,
Below is a minimal test case that always produces the below failure
for me under 0.4.2 but not under 0.4.1,
Cheers
Dave
==
ERROR: test_repr (__main__.uScheduledEvent)
--
Traceback (most recent call last):
File ./test_db_minimal.py, line 19, in tearDown
db.session.clear()
File
/usr/local/lib/python2.5/site-packages/SQLAlchemy-0.4.2-py2.5.egg/sqlalchemy/orm/scoping.py,
line 74, in do
return getattr(self.registry(), name)(*args, **kwargs)
File
/usr/local/lib/python2.5/site-packages/SQLAlchemy-0.4.2-py2.5.egg/sqlalchemy/orm/session.py,
line 577, in clear
self._unattach(instance)
File
/usr/local/lib/python2.5/site-packages/SQLAlchemy-0.4.2-py2.5.egg/sqlalchemy/orm/session.py,
line 1039, in _unattach
if instance._sa_session_id == self.hash_key:
AttributeError: 'MonthlyEvent' object has no attribute '_sa_session_id'
--
dbapi_minimal.py --
import datetime, uuid
from sqlalchemy import *
from sqlalchemy.orm import *
session = scoped_session(sessionmaker(autoflush=False,
transactional=True))
mapper = session.mapper
metadata = MetaData()
## Static variables and mappings
EventType_Daily = 0
EventType_Weekly = 1
EventType_Monthly = 2
EventType_Yearly = 3
eventTable = Table(
'event',
metadata,
Column('id', Integer, primary_key=True),
Column('name', String(100), nullable=False, unique=True),
Column('type', Integer, nullable=False),
Column('action', BLOB), # Pickled arguments for running an
action
Column('step', Integer, nullable=False, default=1),
Column('fromDate', DateTime), # None indicates now
Column('untilDate', DateTime), # None indicates forever
Column('monthly_dayofweek', Boolean),
)
scheduledEventTable = Table(
'scheduledevent',
metadata,
Column('id', Integer, primary_key=True),
Column('event_id', Integer, ForeignKey('event.id')),
Column('runtime', DateTime),
)
class Event(object):
def __init__(self, name, action, step=1, fromDate=None,
untilDate=None):
action: Pickled ActionArgument object for running the
event
fromDate : First time to run this event
untilDate : Time at which this event is no longer valid
self.name = name
self.action = action
self.step = step
self.fromDate = fromDate
self.untilDate = untilDate
def next(self, last):
last: most recent timestamp when this event was executed
raise NotImplementedError(Events must provide a next())
def __repr__(self):
return Event type:%s id:%s % (self.typeName, self.id)
class MonthlyEvent(Event):
MonthlyEvent has an additional init arg of dayofweek.
E.G if (dayofweek == True) then do every first Monday
E.G if (dayofweek == False) then do every nth day of the month
[beware choosing a day 28 lest some months skip it]
def __init__(self, name, action, step=1, fromDate=None,
untilDate=None, dayofweek=True):
Event.__init__(self, name, action, step, fromDate, untilDate)
self.dayofweek = dayofweek
def next(self, last):
monthQuot,monthRem = divmod((last.month + self.step), 12)
# Div cycles to 0, so we need to handle this differently
# 0 indicates December in the current year
if monthRem == 0:
monthRem = 12
monthQuot = 0
incMonth = monthRem
incYear = last.year + monthQuot
newTS = datetime.datetime(
year = incYear,
month = incMonth,
day = last.day,
hour = self.fromDate.hour,
minute = self.fromDate.minute,
)
if newTS self.untilDate:
return None
return newTS
class ScheduledEvent(object):
This is an event that is waiting for its runtime to arrive
def __init__(self, event, runtime):
self.event = event
[sqlalchemy] Mapper inheritance and joins
Hi all,
I've got a situation where I want to use inherited mappers, with joins
to other inherited mappers. However I'm getting some weird results
where the following query should show no cat objects, instead I get 2
back for both queries.
Can anyone spot the flaw in my code here ?
The api and test script are transcribed below.
Cheers
D
---
testapi.py
#!/usr/local/bin/python2.5
from sqlalchemy import *
from sqlalchemy.orm import *
session = scoped_session(
sessionmaker(autoflush=False, transactional=True)
)
mapper = session.mapper
metadata = MetaData()
ANIMAL_TYPE_DOG = 1
ANIMAL_TYPE_CAT = 2
animalTable = Table(
'animal',
metadata,
Column('id', Integer, primary_key=True),
Column('type', Integer, nullable=False),
Column('name', String(100), nullable=False),
Column('vet_id', Integer, ForeignKey('vet.id')),
)
vetTable = Table(
'vet',
metadata,
Column('id', Integer, primary_key=True),
Column('type', Integer, nullable=False),
Column('address', String(100), nullable=False),
Column('kennel', Boolean, nullable=False),
)
class _Animal(object):
def printName(self):
print self.name
class Cat(_Animal):
pass
class Dog(_Animal):
pass
class _Vet(object):
def printAddress(self):
print self.address
class CatVet(_Vet):
pass
class DogVet(_Vet):
pass
animalMapper = mapper(
_Animal,
animalTable,
polymorphic_on=animalTable.c.type,
)
mapper(
Dog,
inherits=animalMapper,
polymorphic_identity=ANIMAL_TYPE_DOG,
properties = {
vet: relation(
DogVet,
lazy=False,
)
}
)
mapper(
Cat,
inherits=animalMapper,
polymorphic_identity=ANIMAL_TYPE_CAT,
properties = {
vet: relation(
CatVet,
lazy=False,
)
}
)
vetMapper = mapper(
_Vet,
vetTable,
polymorphic_on=vetTable.c.type,
)
mapper(
DogVet,
inherits=vetMapper,
polymorphic_identity=ANIMAL_TYPE_DOG,
)
mapper(
CatVet,
inherits=vetMapper,
polymorphic_identity=ANIMAL_TYPE_CAT,
)
def connect(uri):
engine = create_engine(uri, strategy=threadlocal)
metadata.bind = engine
return engine
def create():
metadata.create_all()
def drop():
metadata.drop_all()
test.py
#!/usr/local/bin/python2.5
import testapi as db
DB = sqlite:///test.db
db.connect(DB)
db.create()
v1 = db.DogVet()
v1.address = 12 Foo St
v1.kennel = True
v2 = db.CatVet()
v2.address = 29 Bar Rd
v2.kennel = False
v3 = db.CatVet()
v3.address = 29 Bar Rd
v3.kennel = True
c1 = db.Cat()
c1.name = muffin
c1.vet = v2
c2 = db.Cat()
c2.name = bagel
c2.vet = v2
d1 = db.Dog()
d1.name = rex
d1.vet = v1
d2 = db.Dog()
d2.name = bill
d2.vet = v1
db.session.flush()
print db.Query(db.Cat).filter(db.CatVet.kennel == True).all()
print db.Query(db.Cat).filter(db.CatVet.kennel == False).all()
db.drop()
db.session.flush()
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[sqlalchemy] Mapper properties and a callback
Hi all,
I have a situation where I want to declare a relation between two
tables, but I want to be able to run a callback whenever I append to
that relation. Here's an example
class Kennel:
def callback(self, o):
print callback, o
mapper = Mapper(
Kennel,
kennelTable,
properties = {
dogs : relation(
Dog, cascade=all, delete-orphan
),
}
)
So whenever I use mykennel.dogs.append(fred) I want to be able to tell
the relation to call callback() so that I can do some checking on the
object that is being appended.
Is this possible ??
Cheers
Dave
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[sqlalchemy] Deprecation error raised for query on singly inherited table query ?
Hi all,
The following is a stripped down use case that I have, where I use
single table inheritance and run a query.first(), however I get a
deprecation warning and I was wondering why ??
Cheers
Dave
% cat db.py
from sqlalchemy import *
from sqlalchemy.orm import *
session = scoped_session(
sessionmaker(
autoflush=False,
transactional=True
)
)
mapper = session.mapper
metadata = MetaData()
myTable = Table(
'mytable',
metadata,
Column('id', Integer, primary_key=True),
Column('animate', Boolean, nullable=False),
Column('remoteid', String(50), nullable=False),
)
class MyTable(object): pass
class MyAnimateTable(MyTable): pass
myTableMapper = mapper(
MyTable,
myTable,
polymorphic_on=myTable.c.animate
)
mapper(
MyAnimateTable,
inherits=myTableMapper,
polymorphic_identity=True,
)
def connect(uri):
engine = create_engine(uri, strategy=threadlocal)
metadata.bind = engine
return engine
def create():
metadata.create_all()
def drop():
metadata.drop_all()
% cat test.py
from db import *
connect('sqlite://memory')
drop()
create()
klass = MyAnimateTable
Query(klass).filter(klass.remoteid == fds).first()
Deprecation warning:
/usr/lib/python2.5/site-packages/SQLAlchemy-0.4.1dev_r3765-py2.5.egg/sqlalchemy/sql/expression.py:1231:
SADeprecationWarning: passing in_ arguments as varargs is deprecated,
in_ takes a single argument that is a sequence or a selectable
return self._in_impl(operators.in_op, operators.notin_op, *other)
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[sqlalchemy] 'Column' object has no attribute 'tables'
Hi all,
I'm just working on upgrading my db code to use the new 0.4 api, and
I've hit a problem
Based on the following table def (there's lots more in there, but I've
commented everything out but this table and am still getting the same
error),
sysMessageTable = Table(
'sysmessage',
Column('id', Integer, primary_key=True),
Column('timestamp', DateTime, nullable=False,
default=datetime.datetime.now()),
Column('summary', String(100), nullable=False),
Column('message', TEXT()),
Column('viewed', Boolean, nullable=False, default=False),
when I import my db.py file (literally at the time of import), I get
this error,
Traceback (most recent call last):
File scripts/testdata, line 7, in module
from mymod.db import *
File ./mymod/db.py, line 129, in module
Column('viewed', Boolean, nullable=False, default=False),
File
/usr/lib/python2.5/site-packages/SQLAlchemy-0.4.0dev_r3150-py2.5.egg/sqlalchemy/schema.py,
line 146, in __call__
table = metadata.tables[key]
AttributeError: 'Column' object has no attribute 'tables'
Any suggestions ?
Cheers
Dave
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