[sqlalchemy] Re: ProgrammingError and Catching an Exception
I don't know of a way to do what you're asking. However, you could simply create your own constructor for MyDBLog which truncates the string if it is too long. Barry - Original Message From: Eoghan Murray [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Thursday, September 11, 2008 7:21:39 AM Subject: [sqlalchemy] ProgrammingError and Catching an Exception Hi, I've the following which generates an insert: try: MyDBLog( myfield='A too long string ' ) except Exception, e: log.error(Exception occurred with database logging: %s % e) Unfortunately, 'myfield' is (for example) a string of only length 10, so the session fails with ProgrammingError: (ProgrammingError) value too long for type character varying(10) This error occurs at session commit time, so my 'except' clause above is useless. As 'MyDBLog' is not critical, I want to be able to ignore/log any kind of Exception which the 'try' block above ultimately generates. Is there a way to do this? Thanks! Eoghan --~--~-~--~~~---~--~~ 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: Pickling/unpickling mapped class
I use Gnosis Utils for a similar purpose. The API is similar to pickle, but if you need to control the details of the serialization (which fields get serialized and how), then that is quite different. Gnosis has a concept called mutators for this. Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Friday, June 27, 2008 9:56:59 AM Subject: [sqlalchemy] Re: Pickling/unpickling mapped class On Jun 27, 2008, at 3:25 AM, Nabla wrote: Is there some easy solution of this problem? yes, the receiving application needs to have the same mapper() setup as the sender. If you use the declarative extension to setup your classes, this task is made easier. And additional question - is there some simple way how to convert (marshal, serialize) reflected sqlalchemy class to human- readable XML? we dont have an XML serializer but there might be something on Pypi for that. --~--~-~--~~~---~--~~ 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: Multiple SQLAlchemy DB usage in TurboGears
The identity and visit stuff is pluggable, i.e. you can replace the existing components without hackery; just write your own and specify which one to use in the application .cfg file. This probably sounds more intimidating than it is; the code is really pretty straightforward and you can use their implementations as a starting point. You might consider using a single (separate) database to store all visit information for *all* the customers combined. Your visit schema could have an additional 'customer' column to distinguish which database to use for everything else. Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Thursday, May 8, 2008 5:05:22 PM Subject: [sqlalchemy] Re: Multiple SQLAlchemy DB usage in TurboGears On May 8, 2008, at 11:15 AM, Bobby Impollonia wrote: I'd try bypassing their SQLA integration altogether if thats possible It isn't possible if you are relying on the turbogears identity system (cookie-based visitor tracking and access control). that sounds like a particular set of mappings and classes. theres no issue using those; I was talking about their Session integration. Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ --~--~-~--~~~---~--~~ 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: Duplication of rows in many-to-many relationship
By chance, in your mappers, are you declaring two relationships instead of one relation with a backref? As a side note, once you straighten this out, you may want to declare the composite (a_id, b_id) as a unique key on the relation table. Barry - Original Message From: Karlo Lozovina [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Sunday, May 4, 2008 4:31:55 PM Subject: [sqlalchemy] Duplication of rows in many-to-many relationship Let's say I have two classes A and B, and I want instances of both classes, to have a list of each other, that is, many-to-many relationship. For a shorthand, a means instance of A, and b is an instance of B. For example: a.bs is a list, full of instances of class B. Similarly, b.as is a list, full of instances of class A. In modelling that relationship I use three tables, one for As, one for Bs, and one for their relationship. If I only append instances of B to some a.bs, then save all those objects, everything works fine. But if I append instances of A and B, both to a.bs and b.as, then save, I get double rows in the third table. Is there a way around that? P.S. In a very likely case I haven't been completely understood, I'll attach some code to demonstrate my point ;). Thanks all. Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ --~--~-~--~~~---~--~~ 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: Duplication of rows in many-to-many relationship
With a backref, both ends of the relationship are aware of each other -- if you append object b1 to the collection a.b, then a backref b1.a will be updated immediately. If you had two different relationships, you wouldn't see an update to b1.a until you reload the object. It seems like it'd be nice if they worked the same -- perhaps there's a good reason it doesn't. I think 0.4 has an error check for some cases of mutual relationships (A-B, B-A). Maybe the check is not in place for M:N relationships? Barry - Original Message From: Bobby Impollonia [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Sunday, May 4, 2008 5:28:56 PM Subject: [sqlalchemy] Re: Duplication of rows in many-to-many relationship I thought that defining relation with a backref was just a convenient shorthand for defining two relations. This makes it sound like are practical differences between the two techniques. Is this true? What are the differences? Also, does having the unique key that you recommend stop SA from trying to add the duplicate? Or will it try anyway and then get a SQL exception due to the violated constraint? I am often doing if a not in b.as: b.as.append(a) and I have been wondering if there is a way to just do: b.as.append(a) and have SA automatically check if it was already in collection and shouldn't be added again. On Sun, May 4, 2008 at 4:40 PM, Barry Hart [EMAIL PROTECTED] wrote: By chance, in your mappers, are you declaring two relationships instead of one relation with a backref? As a side note, once you straighten this out, you may want to declare the composite (a_id, b_id) as a unique key on the relation table. Barry - Original Message From: Karlo Lozovina [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Sunday, May 4, 2008 4:31:55 PM Subject: [sqlalchemy] Duplication of rows in many-to-many relationship Let's say I have two classes A and B, and I want instances of both classes, to have a list of each other, that is, many-to-many relationship. For a shorthand, a means instance of A, and b is an instance of B. For example: a.bs is a list, full of instances of class B. Similarly, b.as is a list, full of instances of class A. In modelling that relationship I use three tables, one for As, one for Bs, and one for their relationship. If I only append instances of B to some a.bs, then save all those objects, everything works fine. But if I append instances of A and B, both to a.bs and b.as, then save, I get double rows in the third table. Is there a way around that? P.S. In a very likely case I haven't been completely understood, I'll attach some code to demonstrate my point ;). Thanks all. Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ --~--~-~--~~~---~--~~ 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: Duplication of rows in many-to-many relationship
My fault - when I said there was an error check, it was for the case where you declare relationships A-B and B-A both with backrefs. Here's the thread from about six months ago: http://groups.google.com/group/sqlalchemy/browse_thread/thread/420b7de79119ad4d/8e8311bfd18d05e2?lnk=gstq=barry+hart#8e8311bfd18d05e2). Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Sunday, May 4, 2008 10:31:10 PM Subject: [sqlalchemy] Re: Duplication of rows in many-to-many relationship On May 4, 2008, at 8:59 PM, Barry Hart wrote: With a backref, both ends of the relationship are aware of each other -- if you append object b1 to the collection a.b, then a backref b1.a will be updated immediately. If you had two different relationships, you wouldn't see an update to b1.a until you reload the object. It seems like it'd be nice if they worked the same -- perhaps there's a good reason it doesn't. I think 0.4 has an error check for some cases of mutual relationships (A-B, B-A). Maybe the check is not in place for M:N relationships? we dont really have any check of A-B / B-A being present without a backref. the backref is technically not needed for a bidirectional o2m/m2o relationship, unless the post_update option is being used. for the m2m, its explicitly needed since only one side needs to handle the association table, and the other side needs to be made aware of that. we've yet to try working up some alarms for this sort of thingits probably not that hard to do so (for every secondary table, look it up in a registry, see if its mapped, etc). Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ --~--~-~--~~~---~--~~ 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: VIEW names?
SA to be (i.e. would View act read-only, etc.. though I guess VIEWs aren't necessarily purely read-only in some cases ?). Right. For example, I think SQL Server views are updateable to some extent (depending on whether there's a table primary key in the column list, whether there are joins, etc.) The rules for this are almost certainly DB-specific, too. Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Friday, January 25, 2008 7:42:10 PM Subject: [sqlalchemy] Re: VIEW names? On Jan 25, 2008, at 7:25 PM, Martin wrote: Hello, since I didn't find a direct way to create a VIEW within SQLalchemy v0.4, I use the text-feature to do that with a SQL/DDL statement, which is maybe not elegant, but works... Is there a way to get information about Views? (Which Views exist and which columns do they provide?) we dont provide a function for this currently. adding reflection for views is not a big deal, but the decision to be made is how it would be expressed in the API, either as Table(, view=True), or View(...). we'd have to decide how view-aware we want SA to be (i.e. would View act read-only, etc.. though I guess VIEWs aren't necessarily purely read-only in some cases ?). Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping --~--~-~--~~~---~--~~ 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: Select entire column
Is this what you want?
select([my_table.c.my_column], distinct=True)
Barry
- Original Message
From: JamesT [EMAIL PROTECTED]
To: sqlalchemy sqlalchemy@googlegroups.com
Sent: Wednesday, November 7, 2007 2:05:13 AM
Subject: [sqlalchemy] Select entire column
I am looking to filter specific columns in a table, but I cannot find
how to do this. I can filter by setting these columns to a value, but
not just grabbing the entire column. In SQL, I want to do this:
SELECT artist FROM artist_table, where the only column kept is
artist. The reason I want to do this is so that I can run a distinct()
on the Query object returned to get the distinct artists and also
distinct genres. Here is a sample of what I am doing now without
filtering to get the data I need:
tuples = Session.query(Albums).add_entity(Songs).join('songs').all()
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[sqlalchemy] Re: associative table with extra field
I would've declared the relation from Country to CountryLanguage, not vice
versa, but I doubt that is the reason for your error.
Can you provide a full example which reproduces the error?
Barry
- Original Message
From: mmstud [EMAIL PROTECTED]
To: sqlalchemy sqlalchemy@googlegroups.com
Sent: Saturday, October 27, 2007 8:02:38 AM
Subject: [sqlalchemy] associative table with extra field
I'm trying to implement associative table with extra field on join
table, but faced problems... what is it, that im doing wrong here,
because i get python error:
.
.
.
2007-10-27 14:58:26,816 INFO sqlalchemy.engine.base.Engine.0x..d0 {}
2007-10-27 14:58:26,816 INFO sqlalchemy.engine.base.Engine.0x..d0
COMMIT
ERROR: Internal Python error in the inspect module.
Below is the traceback from this internal error.
Traceback (most recent call last):
File /usr/lib/python2.4/site-packages/IPython/ultraTB.py, line
462, in text
records = _fixed_getinnerframes(etb, context,self.tb_offset)
File /usr/lib/python2.4/site-packages/IPython/ultraTB.py, line
118, in _fixed_getinnerframes
records = inspect.getinnerframes(etb, context)
File inspect.py, line 804, in getinnerframes
framelist.append((tb.tb_frame,) + getframeinfo(tb, context))
File inspect.py, line 768, in getframeinfo
lines, lnum = findsource(frame)
File inspect.py, line 437, in findsource
if pat.match(lines[lnum]): break
IndexError: list index out of range
Unfortunately, your original traceback can not be constructed.
*
countries_table = Table(countries, metadata,
Column(id, Integer, primary_key=True),
Column(alpha2, String(2)),
Column(alpha3, String(3)),
Column(name, Unicode(100)),
)
# association table with additional field
countries_languages = Table(countries_languages, metadata,
Column(country_id, Integer, ForeignKey('countries.id')),
Column(language_id, Integer, ForeignKey('languages.id')),
Column(is_primary, Boolean, default=False), # only one can be
default at time
)
languages_table = Table(languages, metadata,
Column(id, Integer, primary_key=True),
Column(alpha2, String(2)),
Column(name, Unicode(100)),
)
class BaseObject(object):
def __init__(self):
self._repr_ = []
def __repr__(self):
from string import join
str = ', '.join('%s' % (self.__dict__[v]) for v in
self._repr_)
return %s(%s) % (self.__class__, str)
class NameObject(BaseObject):
def __init__(self, name):
self.name = name
BaseObject.__init__(self)
def __repr__(self):
self._repr_ = [name]
return BaseObject.__repr__(self)
class Country(NameObject):
def __init__(self, alpha2, alpha3, name):
NameObject.__init__(self, name)
self.alpha2 = alpha2
self.alpha3 = alpha3
class CountryLanguage(object):
def __init__(self, is_primary = False):
self.is_primary = is_primary
class Language(NameObject):
def __init__(self, alpha2, name):
NameObject.__init__(self, name)
self.alpha2 = alpha2
mapper(Country, countries_table, properties={
'post_offices':relation(PostOffice, backref='country'), # one to
many
'languages':relation(CountryLanguage, backref='country'), # many
to many
}
)
mapper(CountryLanguage, countries_languages, properties={
'language':relation(Language, backref=countries)
}
)
mapper(Language, languages_table)
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[sqlalchemy] Re: associative table with extra field
You need to add an ID column to your countries_languages table, like this:
Column(id, Integer, primary_key=True),
Alternatively you could declare the combination country_id and language_id as
your primary key.
Barry
- Original Message
From: mmstud [EMAIL PROTECTED]
To: sqlalchemy sqlalchemy@googlegroups.com
Sent: Saturday, October 27, 2007 3:53:47 PM
Subject: [sqlalchemy] Re: associative table with extra field
That was a good tip. Now i get:
2007-10-27 22:49:25,454 INFO sqlalchemy.engine.base.Engine.0x..90 {}
2007-10-27 22:49:25,455 INFO sqlalchemy.engine.base.Engine.0x..90
COMMIT
Traceback (most recent call last):
File stdin, line 1, in ?
File fixtures.py, line 4, in ?
from mappers import *
File mappers.py, line 39, in ?
mapper(CountryLanguage, countries_languages, properties={
File build/bdist.linux-x86_64/egg/sqlalchemy/orm/__init__.py, line
516, in mapper
File build/bdist.linux-x86_64/egg/sqlalchemy/orm/mapper.py, line
152, in __init__
File build/bdist.linux-x86_64/egg/sqlalchemy/orm/mapper.py, line
414, in _compile_tables
sqlalchemy.exceptions.ArgumentError: Could not assemble any primary
key columns for mapped table 'countries_languages'
I'll provide more full example tomorrow...
Thanks.
On Oct 27, 6:44 pm, Michael Bayer [EMAIL PROTECTED] wrote:
On Oct 27, 2007, at 8:02 AM, mmstud wrote:
I'm trying to implement associative table with extra field on join
table, but faced problems... what is it, that im doing wrong here,
because i get python error:
try not using IPython. shells like IDLE etc. always seem to corrupt
things. at the very least, youll get a real stack trace.
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[sqlalchemy] Re: In a many to many relationship how to access some properties of that relationship
No, the association proxy would be used if you want to let users directly access movies or vice versa. To get the score, you can define a mapper for movie_vote table and define relationships between it and users and movies. Barry - Original Message From: Jason [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Tuesday, October 23, 2007 7:10:15 PM Subject: [sqlalchemy] In a many to many relationship how to access some properties of that relationship Greetings, for my model I have this: user_table=Table(users, metadata, Column(id, Integer, primary_key=True), Column(gender, Unicode), Column(age, Integer, ForeignKey(ages.id)), Column(occupation, Integer, ForeignKey(occupations.id)), Column(zipCode, Integer(5)) ) movie_table=Table(movies, metadata, Column(id, Integer, primary_key=True), Column(title, Unicode) ) movie_vote_table=Table(movie_votes, metadata, Column(id, Integer, primary_key=True), Column(user, Integer, ForeignKey(users.id)), Column(movie, Integer, ForeignKey(movies.id)), Column(score, Float) ) I've of course left out some of the other tables that weren't needed for this question so I of course a many to many relationship between the users and the movies they have rated. but the only problem is how do I access that score? It would be cool to have something like User.movies[0].score, User.movies[1].score .. etc. is this something I would want to use the association proxy for? -Jason __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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: Problem when slicing a relation list
Here is a test case for the bug. The bug only manifests itself if the
transaction that slices the list also modifies all the remaining objects in the
list.
Barry
- Original Message
From: Michael Bayer [EMAIL PROTECTED]
To: sqlalchemy@googlegroups.com
Sent: Wednesday, October 24, 2007 5:01:43 PM
Subject: [sqlalchemy] Re: Problem when slicing a relation list
hey Barry -
again, can you please attach a working test case for this one ? attached is
mine, which tests this exact operation for four diferent kinds of relation()s -
one-to-many and many to many, with and without delete cascade on the relation.
passes for 0.3 (including 0.3.10) and 0.4.
-Inline Attachment Follows-
from sqlalchemy import *
from sqlalchemy.orm import *
def test(m2m=False, cascade=False, useclear=False):
engine = create_engine('sqlite://', echo=True)
meta = MetaData(engine)
a = Table('a', meta, Column('id', Integer, primary_key=True), Column('foo',
String(30)))
if m2m:
b = Table('b', meta, Column('id', Integer, primary_key=True),
Column('foo', String(30)))
else:
b = Table('b', meta, Column('id', Integer, primary_key=True),
Column('foo', String(30)), Column('a_id', Integer, ForeignKey('a.id')))
if m2m:
atob = Table('atob', meta, Column('a_id', Integer, ForeignKey('a.id')),
Column('b_id', Integer, ForeignKey('b.id')), )
else:
atob = None
class A(object):
def __init__(self, foo):
self.foo = foo
class B(object):
def __init__(self, foo):
self.foo = foo
if cascade:
use_cascade = all, delete-orphan
else:
use_cascade = save-update
mapper(A, a, properties={
'bs':relation(B, secondary=atob, cascade=use_cascade)
})
mapper(B, b)
meta.create_all()
a1 = A('a1')
a1.bs.append(B('b1'))
a1.bs.append(B('b2'))
a1.bs.append(B('b3'))
sess = create_session()
sess.save(a1)
sess.flush()
if m2m:
assert atob.count().scalar() == 3
else:
assert b.count(b.c.a_id == None).scalar() == 0
assert b.count().scalar() == 3
if useclear:
sess.clear()
a1 = sess.query(A).get(a1.id)
assert len(a1.bs) == 3
a1.bs = a1.bs[1:]
sess.flush()
if m2m:
assert atob.count().scalar() == 2
else:
assert b.count(b.c.a_id != None).scalar() == 2
if cascade:
assert b.count().scalar() == 2
else:
assert b.count().scalar() == 3
if useclear:
sess.clear()
a1 = sess.query(A).get(a1.id)
assert len(a1.bs) == 2
for m2m in (True, False):
for cascade in (True, False):
for useclear in (True, False):
test(m2m, cascade, useclear)
On Oct 24, 2007, at 4:18 PM, Barry Hart wrote:
I found a problem in SqlAlchemy 0.3.10 this week: slicing a list property
caused the whole association list to be deleted. For example, suppose I want to
remove the first 3 items from a list of related items:
my_obj.related = my_obj.related[3:]
When these changes were saved , my_obj.related was empty the next time it
loaded. This code, however, worked correctly:
for i in range(0, 3):
del my_obj.related[0]
Barry
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from sqlalchemy import *
from sqlalchemy.ext.assignmapper import assign_mapper
import sqlalchemy
from sqlalchemy.ext import activemapper, sessioncontext
import datetime
engine = None
def create_engine():
global engine
engine = sqlalchemy.create_engine('sqlite://')
#engine = sqlalchemy.create_engine('postgres://postgres:[EMAIL
PROTECTED]:5432/testdb')
metadata.connect(engine)
def create_session():
return sqlalchemy.create_session(bind_to=engine)
def fuzzy_search(column, value):
Case insensitive search allowing partial string matches.
return func.lower(column).like('%%%s%%' % value.lower())
metadata = activemapper.metadata
create_engine()
session = activemapper.Objectstore(create_session)
activemapper.objectstore = session
g_count = 10
##
# Classes
[sqlalchemy] Re: Problem when slicing a relation list
Credit for this one goes to my colleague Greg Hunt. All I did was tell him to write a test case. :-) Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Thursday, October 25, 2007 6:16:24 PM Subject: [sqlalchemy] Re: Problem when slicing a relation list On Oct 25, 2007, at 3:58 PM, Barry Hart wrote: Here is a test case for the bug. The bug only manifests itself if the transaction that slices the list also modifies all the remaining objects in the list. hi barry - nice job again. we've narrowed down the specific mechanism in this in ticket #834. thanks ! __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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] Declaring a relationship twice - could SqlAlchemy auto-detect problems like this?
This subject came up on the TurboGears list and someone suggested I post here. I noticed a while back that in SqlAlchemy 0.3.x, if you have two mapped classes A and B, and you define the same relationship (with a backref) on both classes, you won't get an error message but the two relationships interfere with each other. For example, you might set the value of the relationship and it won't be saved to the database. Would it be possible to detect and flag this as an error at model compilation time? Perhaps there are other model problems like this which could be detected automatically. If so, I think it would really flatten the learning curve for SqlAlchemy newbies. Barry __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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] Problem when slicing a relation list
I found a problem in SqlAlchemy 0.3.10 this week: slicing a list property caused the whole association list to be deleted. For example, suppose I want to remove the first 3 items from a list of related items: my_obj.related = my_obj.related[3:] When these changes were saved , my_obj.related was empty the next time it loaded. This code, however, worked correctly: for i in range(0, 3): del my_obj.related[0] Barry __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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: Declaring a relationship twice - could SqlAlchemy auto-detect problems like this?
Here's what I had in mind. This set of mappings compiles without errors in
0.3.11:
from sqlalchemy import *
from sqlalchemy.orm import *
engine = create_engine('sqlite://')
meta = MetaData(engine)
a = Table('a', meta, Column('id', Integer, primary_key=True))
b = Table('b', meta, Column('id', Integer, primary_key=True), Column('a_id',
Integer, ForeignKey('a.id')))
class A(object):pass
class B(object):pass
class C(object):pass
mapper(A, a, properties={
'b':relation(B, backref='a')
})
mapper(B, b, properties={
'a':relation(A, backref='b')
})
compile_mappers()
Barry
- Original Message
From: Michael Bayer [EMAIL PROTECTED]
To: sqlalchemy@googlegroups.com
Sent: Wednesday, October 24, 2007 4:41:46 PM
Subject: [sqlalchemy] Re: Declaring a relationship twice - could SqlAlchemy
auto-detect problems like this?
On Oct 24, 2007, at 4:16 PM, Barry Hart wrote:
This subject came up on the TurboGears list and someone suggested I post here.
I noticed a while back that in SqlAlchemy 0.3.x, if you have two mapped classes
A and B, and you define the same relationship (with a backref) on both classes,
you won't get an error message but the two relationships interfere with each
other. For example, you might set the value of the relationship and it won't be
saved to the database. Would it be possible to detect and flag this as an error
at model compilation time?
hey Barry -
that would be a bug, and I cant reproduce it, at least the bug i think youre
describing, in neither 0.3 nor 0.4:
from sqlalchemy import *
from sqlalchemy.orm import *
engine = create_engine('sqlite://')
meta = MetaData(engine)
a = Table('a', meta, Column('id', Integer, primary_key=True))
b = Table('b', meta, Column('id', Integer, primary_key=True), Column('a_id',
Integer, ForeignKey('a.id')))
c = Table('c', meta, Column('id', Integer, primary_key=True), Column('a_id',
Integer, ForeignKey('a.id')))
class A(object):pass
class B(object):pass
class C(object):pass
mapper(A, a)
mapper(B, b, properties={
'a':relation(A, backref='thebackref')
})
mapper(C, c, properties={
'a':relation(A, backref='thebackref')
})
compile_mappers()
output:
stack trace
sqlalchemy.exceptions.ArgumentError: Backrefs do not match: backref
'thebackref' expects to connect to class '__main__.C', but found a backref
already connected to class '__main__.B'
can you produce a test case ?
__
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[sqlalchemy] Re: Declaring a relationship twice - could SqlAlchemy auto-detect problems like this?
That is awesome -- thanks. I would've reported it sooner, but I thought maybe I was the only one silly enough to make these mistakes in my mappers. :-) Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Wednesday, October 24, 2007 7:26:39 PM Subject: [sqlalchemy] Re: Declaring a relationship twice - could SqlAlchemy auto-detect problems like this? On Oct 24, 2007, at 5:02 PM, Barry Hart wrote: Here's what I had in mind. This set of mappings compiles without errors in 0.3.11: from sqlalchemy import * OK, thanks very much for pointing this one out, as it came across a big heap of egregious cruft in the backref code which I graciously flattened (it even included the phrase if not x is not None...so embarrassing...). It also raised a few surprises as there were a very small number of unit tests that were actually defining conflicting properties in this manner...so when people upgrade to 0.4.1 some people might get a few surprises (that alone makes it more controversial of a candidate for the 0.3 series, which is in maintenance mode). changeset is rev 3660. __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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: multiple inserts of sqlalchemy instances?
I've written code similar to this with no problems. Are you using assign_mapper? If so, the save() call is unnecessary. Do you get this error on the first object or on some subsequent object? Barry - Original Message From: Lukasz Szybalski [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Monday, October 22, 2007 3:54:03 PM Subject: [sqlalchemy] multiple inserts of sqlalchemy instances? Hello, I need to save data multiple times in a for loop. I was trying to do something like this: You are able to select which group you want to be in: A,B,C,D for record in userchoice: new=model.User() #set some variables if record.group=='A': #set some more fields new.save() new.flush() elif record.group=='B': #set some more fields new.save() new.flush() If I do that I get: File /usr/lib/python2.4/site-packages/sqlalchemy/orm/mapper.py, line 838, in save_obj raise exceptions.FlushError(New instance %s with identity key %s conflicts with persistent instance %s % (mapperutil.instance_str(obj), str(instance_key), mapperutil.instance_str(existing))) FlushError: New instance [EMAIL PROTECTED] with identity key (class 'XXX.model.User', (19527, None), None) conflicts with persistent instance [EMAIL PROTECTED] Is there a way to do multiple inserts with sqlalchemy? Lucas -- -- Vim auto completion for python http://lucasmanual.com/mywiki/FrontPage#head-8ce19b13e89893059e126b719bebe4ee32fe103c TurboGears from start to finish: http://www.lucasmanual.com/mywiki/TurboGears __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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: Advice on complicated (?) SQL query
Try this for the outer query: s = select([repetition_table.c.grade],(repetition_table.c.rep_number==2) (repetition_table.c.card_key.in_(s_inner)) ) Barry - Original Message From: pbienst [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Saturday, October 20, 2007 6:55:56 AM Subject: [sqlalchemy] Re: Advice on complicated (?) SQL query Thanks! Based on your suggestion, I tried the following: The inner query goes like this: repetition_table_2 = repetition_table.alias() s_inner = select([repetition_table_2.c.card_key], (repetition_table_2.c.rep_number==5) \ (repetition_table_2.c.grade==2)).limit(10) print db_session.execute(s_inner).fetchall() [(3,), (8,), (16,), (34,), (27,), (42,), (33,), (32,), (37,), (36,)] Now for the outer query: s = select([repetition_table.c.grade],(repetition_table.c.rep_number==2) (repetition_table.c.card_key==s_inner) ) print db_session.execute(s).fetchall() [(0,)] I seem to be missing 9 entries... I also tried the following trivial outer query, which I suppose should give me back the results of my inner query: s = select([repetition_table.c.card_key],(repetition_table.c.card_key==s_inner) ) print db_session.execute(s).fetchall() [(3,), (3,), (3,), (3,), (3,), (3,), (3,), (3,)] Obviously, I'm still missing something... Peter __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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: Advice on complicated (?) SQL query
I think you want the final SQL query to look something like this: select * from card_table join repetition_table on repetition_table.card_key = card_table.id where repetition_table.rep_number = 1 and repetition_table.rep_number = 4 and card_table.id in (select ct2.id from card_table AS ct2 join repetition_table AS rt2 on rt2.card_key = ct2.id AND YOUR CUSTOM CONDITIONS HERE) The main difference is that I'm doing a join between card and repetition on both the outer and inner queries. This lets me constrain the join and avoid getting the Cartesian product. Barry - Original Message From: pbienst [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Thursday, October 18, 2007 7:48:36 AM Subject: [sqlalchemy] Advice on complicated (?) SQL query Hi, I have a query which works fine through the ORM, albeit a bit slow, so I want to drop down to the SQL layer to speed things up. However, being an SQL novice, I can't seem to figure out how to get it to work. I have a database containing the history of repetitions with a flash card program. I have a table containing the flash cards, and a second table containing the details of all the repetitions for all the flashcards. I want to look at all cards where repetition 5 obeys certain criteria, and then for these cards look at repetitions 1 to 4. Using the ORM, that's easy enough: repetitions = db_session.query(Repetition).filter((Repetition.rep_number==5) \ (Repetition.grade==2)) for r in repetitions: for index in range(4): print index, r.card.repetitions[index].grade After browsing through the documentation, I have the impression that using aliases could be the way to go. I tried the following code (which would only give me repetition 1 instead of 1 to 4, but a loop is easily made): repetition_table_2 = repetition_table.alias() s = select([repetition_table.c.grade], (repetition_table.c.rep_number==1) \ (repetition_table.c.card_key==repetition_table_2.c.card_key) \ (repetition_table_2.c.rep_number==5) \ (repetition_table_2.c.grade==2)) However, this runs forever, so I'm guessing it escapes into the wonderful world of Cartesian products. Can anybody help me contruct the proper SQL query or otherwise speed up the ORM version? Thanks! Peter Take the Internet to Go: Yahoo!Go puts the Internet in your pocket: mail, news, photos more. http://mobile.yahoo.com/go?refer=1GNXIC --~--~-~--~~~---~--~~ 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: Error combining DISTINCT and ORDER BY in an ORM query on PostgreSQL
why would you be calling add_column() in this case (besides the PG bug workaround) ? We might call it for certain cases when we're building a report/data screen. But 95% of the time we just want normal objects. slice calls instances() yes. Thanks, I'll keep instances() in mind as a possible workaround. Currently we are just encapsulating the TurboGears @paginate decorator. This is not as generic but works reasonable well. Barry Yahoo! oneSearch: Finally, mobile search that gives answers, not web links. http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC --~--~-~--~~~---~--~~ 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: Error combining DISTINCT and ORDER BY in an ORM query on PostgreSQL
I've started using add_column() as needed to work around this. Our application
tends to have a single, fairly generic filter_sort function for each class.
Some use cases of this function require add_column() and some don't. From the
caller's perspective, the filter_sort() function is poorly encapsulated because
sometimes it sometimes returns objects and sometimes tuples.
It'd be very helpful if the add_column() function took an optional parameter
'omit_from_results' telling whether the column should be included in the
results, then our filter_sort() functions could always return objects.
Barry
- Original Message
From: Barry Hart [EMAIL PROTECTED]
To: sqlalchemy@googlegroups.com
Sent: Thursday, September 6, 2007 1:55:14 PM
Subject: Re: [sqlalchemy] Re: Error combining DISTINCT and ORDER BY in an ORM
query on PostgreSQL
add_column() worked great, thanks!
Barry
- Original Message
From: Michael Bayer [EMAIL PROTECTED]
To: sqlalchemy@googlegroups.com
Sent: Thursday, September 6, 2007 10:18:58 AM
Subject: [sqlalchemy] Re: Error combining DISTINCT and ORDER BY in an ORM query
on PostgreSQL
the two immediate ways to do this with ORM are to use add_column() on Query, or
to query from a fully constructed select() statement. The former will have the
effect of returning tuples containing the instance as well as the additional
columns, the latter doesnt play as nicely with eager loading.add_column()
is probably the better
option here.
On Sep 6, 2007, at 9:09 AM, Barry Hart wrote:
My application has the following data model:
A promotion has 1 mechanic.
A promotion has 0 or more products.
I want to query for a list of promotions containing products whose name matches
a pattern, and I want the resulting list to be sorted by a property on the
promotion's mechanic.
This query does not work with SQLAlchemy 0.3.10 on PostgreSQL 8.1. It's because
of the combination of using DISTINCT and ORDER BY on an table external to the
main table for the object. (The use of DISTINCT is necessary because joining
with the products table creates duplicate records. I'm
showing the query results in a web application with 'n' records per page.
Without DISTINCT, the ORM mapper will ignore the duplicates, but the record
count for the query no longer reflects the actual number of objects to be
returned, making it impractical to page through the data.)
The error is the following:
sqlalchemy.exceptions.SQLError: (ProgrammingError) for SELECT DISTINCT, ORDER BY
expressions must appear in select list
'SELECT DISTINCT promo_promotion.mechanic_id AS promo_promotion_mechanic_id, pr
omo_promotion.id AS promo_promotion_id, promo_promotion.name AS promo_promotion_
name \nFROM promo_promotion JOIN prod_product ON promo_promotion.id = prod_produ
ct.promotion_id JOIN promo_mechanic ON promo_mechanic.id = promo_promotion.mecha
nic_id \nWHERE
lower(prod_product.name) LIKE %(lower)s ORDER BY promo_mechanic.n
ame ASC' {'lower': '%1%'}
The same program works fine on SQLite.
I could write a similar query at the relational level that explicitly includes
the sort field, but I'd prefer to work at the ORM level. Is there a way to do
this?
My
test case is below.
Barry H.
--
from sqlalchemy import *
from sqlalchemy.ext.assignmapper import assign_mapper
import sqlalchemy
from sqlalchemy.ext import activemapper, sessioncontext
engine = None
def create_engine():
global engine
#engine = sqlalchemy.create_engine('sqlite://')
engine = sqlalchemy.create_engine('postgres://postgres:[EMAIL
PROTECTED]:5432/testdb')
metadata.connect(engine)
def create_session():
return sqlalchemy.create_session(bind_to=engine)
def fuzzy_search(column,
value):
Case insensitive search allowing partial string matches.
return func.lower(column).like('%%%s%%' % value.lower())
metadata = activemapper.metadata
create_engine()
session = activemapper.Objectstore(create_session)
activemapper.objectstore = session
##
# Classes
##
class Mechanic(object): pass
class Promotion(object):
def __repr__(self):
return 'Promotion: %s, mechanic=%s' % (self.name, self.mechanic.name)
class Product(object): pass
##
# Tables
##
mechanic_table = Table(
'promo_mechanic', metadata,
Column('id', Integer, primary_key=True),
Column('name', Unicode, unique=True))
promotion_table = Table(
'promo_promotion', metadata,
Column('id', Integer, primary_key=True),
Column('name', Unicode, unique=True),
Column('mechanic_id', Integer, ForeignKey('promo_mechanic.id')))
product_table = Table(
'prod_product', metadata,
Column('id', Integer, primary_key=True),
Column('name',
Unicode
[sqlalchemy] Does the SQL construction language support 'INSERT INTO' from a SELECT?
I have an insert query in SQL where the records to be inserted are computed from a SELECT. Can I build this query in the SqlAlchemy query construction language? INSERT INTO product_current_promotion (promotion_id, product_id) SELECT promo_promotion.id, promo_promotion_items.product_id FROM promo_promotion_items, promo_promotion WHERE promo_promotion.id = promo_promotion_items.promotion_id AND promo_promotion.week_id = 3 One thought is to build the SELECT in SqlAlchemy, loop over that in Python and insert the records that way, but I'd like to make the database do all the work. Barry Be a better Heartthrob. Get better relationship answers from someone who knows. Yahoo! Answers - Check it out. http://answers.yahoo.com/dir/?link=listsid=396545433 --~--~-~--~~~---~--~~ 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: how to retrieve/update data from/on multiple databases
SQLite supports an ATTACH command where multiple databases may be accessed seamlessly using a single connection. Does PostgreSQL have something similar? If so, then perhaps all you'd need is to add a few extra steps when you connect to the database. Barry - Original Message From: Alchemist [EMAIL PROTECTED] To: sqlalchemy sqlalchemy@googlegroups.com Sent: Wednesday, May 30, 2007 9:19:09 AM Subject: [sqlalchemy] how to retrieve/update data from/on multiple databases Working with: Python 2.4 SQLAlchemy 0.3.7 Postgresql 8.2 database servers I am working in a multidatabase environment. I need to perform a query over multiple databases, then manipulate the obtained results and commit my changes in different tables in different databases. How can I query from multiple databases? How can INSERTs/UPDATEs be performed on different tables in different databases? Thank you. Park yourself in front of a world of choices in alternative vehicles. Visit the Yahoo! Auto Green Center. http://autos.yahoo.com/green_center/ --~--~-~--~~~---~--~~ 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: Modifying __dict__ doesn't dirty an instance
Note that not all object 'fields' are present in the dictionary. For example, in our app we may have a SQLAlchemy property '_foo' which is exposed as a Python property 'foo'. In this case I believe '_foo' will be in the dictionary, but your app should probably be working with 'foo'. Barry - Original Message From: Michael Bayer [EMAIL PROTECTED] To: sqlalchemy@googlegroups.com Sent: Thursday, May 17, 2007 6:55:31 PM Subject: [sqlalchemy] Re: Modifying __dict__ doesn't dirty an instance On May 17, 2007, at 5:31 PM, Catherine wrote: I noticed an issue that - well, I honestly don't know whether to call it a bug or not. I need to talk it out with somebody who understands SQLA better. When I retrieve an instance, then alter its attributes by manipulating its __dict__, the instance doesn't get dirtied, and the changes won't be sent to the database when I flush the session. a lot more than that breaks, in fact. I can work around the problem pretty easily, like this: exec(operation, employee.__dict__) employee._state['modified'] = True That change to ._state normally happens in InstrumentedAttribute.__set__ in sqlalchemy/orm/attributes.py (line 263), which gets called for instance.attribute = newvalue, but not for instance.__dict__['attribute'] = newvalue. well _state is a private attribute which isnt guaranteed to stay that way in future versions. I'm wondering if I should just sit on this workaround personally, or dig into figuring out how to modify SQLA so it will always work for __dict__ manipulation. So - is direct manipulation of the __dict__ something that SQLA should support, or would that fall in the realm of you are getting weird on us, you're on your own? I guess that double-underscore sort of implies you're on your own, but __dict__ manipulation doesn't seem overly exotic in practice. the entire method of attribute instrumentation is via property objects added to your classes (in fact they are instances of InstrumentedAttribute). the __dict__ is how to get at the instance attributes while bypassing the attribute instrumentation entirely. while the _state hack works right now, and there is an additional way it might work which would be to set the mutable_scalars flag to True on all the InstrumentedAttribute objects (thereby ignoring the _state flag), both of those methods still break all the cascade functionality and backref functionality, and will also return the wrong list set of deltas in the case of un-lazyloaded attributes that get set directly via __dict__. i.e. the attributes package is largely event-based and theres no event listening on __dict__ directly. a rewrite would involve replacing the __dict__ of all instances with a custom dictionary that does everything, something i understand is a Python no-no (and also makes the instrumentation that much more opaque, since theres no bypass level anymore). the cleanest solution of all is just to replace your call to: myinstance.__dict__ with a proxying dict: class MyDict(dict): def __init__(self, obj): self.obj = obj def __getitem__(self, key): return getattr(self.obj, key) def __setitem__(self, key, value): setattr(self.obj, key, value) def keys(self): return self.obj.__dict__.keys() # etc .. MyDict(myinstance) Don't get soaked. Take a quick peak at the forecast with the Yahoo! Search weather shortcut. http://tools.search.yahoo.com/shortcuts/#loc_weather --~--~-~--~~~---~--~~ 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] Question about overriding properties
In our application's Order table, we have foreign-key fields which reference the persons who placed the order, are responsible for fulfilling the order, etc. For reporting speed, the Order table holds denormalized copies of contact information for these people. Whenever one of the foreign keys is updated, I want to update the denormalized information. I can do this using a Python property, but then I can't use that name in a get_by or select_by. I found a nice example in the SQLAlchemy documentation on how to create synonyms for existing fields, but I don't think that will help me because that would just create a synonym for the ID field, not the object. Is there a way to satisfy both requirements (updating denormalized info when the FK changes, able to query by this property rather than its ID)? I know I could use a database trigger, but I would rather stick with pure Python if possible. Thanks, Barry __ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
