Thread: [SQLObject] Strange bug with SQLObject 0.6
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From: Carlos R. <car...@gm...> - 2004-10-15 21:10:32
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Hello all. I'm writing a prototype using sqlobjects and sqlite, and
I've run into a strange problem. It may be a dumb mistake of mine (as
I often do :-), but I was not able to spot it. This is the test code:
-----
from sqlobject import connectionForURI, SQLObject, StringCol, IntCol, \
FloatCol, ForeignKey, MultipleJoin
db = connectionForURI('sqlite:/work/test.db')
class dbWorkItem(SQLObject):
_connection = db
wi_name = StringCol(length = 60, notNone = True)
wi_description = StringCol(length = 200, notNone = True, default = '')
wi_form_class = StringCol(length = 40, notNone = True)
wi_form_id = IntCol(default=0)
owner = ForeignKey('dbUser')
workflow = ForeignKey('dbWorkFlow')
class dbUser(SQLObject):
_connection = db
user_nickname = StringCol(length = 15, notNone = True, alternateID = True)
user_password = StringCol(length = 15, notNone = True, default = '')
user_name = StringCol(length = 40, notNone = True, default = '')
user_address1 = StringCol(length = 40, notNone = False, default = '')
user_address2 = StringCol(length = 40, notNone = False, default = '')
user_city = StringCol(length = 40, notNone = False, default = '')
user_comments = StringCol(length = 400, notNone = False, default = '')
workitems = MultipleJoin('dbWorkItem')
def new_db():
dbUser.createTable()
dbWorkItem.createTable()
dbUser(user_nickname="cribeiro", user_name="Carlos Ribeiro")
dbWorkItem(wi_name='task1', wi_description='Task 1',
wi_form_class='', workflow=None, owner=1)
dbWorkItem(wi_name='task2', wi_description='Task 2',
wi_form_class='', workflow=None, owner=1)
>>> new_db()
>>> u = dbUser.get(1)
>>> u
<dbUser 1 user_address1='' user_password='' user_address2=''
user_city='' user_name='Carlos Ribeiro' user_nickname='cribeiro'
user_comments=''>
>>> u.workitems
Traceback (most recent call last):
File "<interactive input>", line 1, in ?
AttributeError: 'dbUser' object has no attribute 'workitems'
>>> u.user_name
'Carlos Ribeiro'
>>> wi = dbWorkItem.get(1)
>>> wi
<dbWorkItem 1 wi_form_class='' wi_form_id=0 wi_name='Entra nota
fiscal' workflowID=None ownerID=1 wi_description='Entra nota fiscal'>
>>> wi.owner
<dbUser 1 user_address1='' user_password='' user_address2=''
user_city='' user_name='Carlos Ribeiro' user_nickname='cribeiro'
user_comments=''>
>>> wi.owner is u
True
For some reason, I cant access the dbUser.workitems property. I tried
the example provided in the documentation (using Person and Address
entities), and it works. What am I missing here?
--
Carlos Ribeiro
Consultoria em Projetos
blog: http://rascunhosrotos.blogspot.com
blog: http://pythonnotes.blogspot.com
mail: car...@gm...
mail: car...@ya...
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From: Michel T. <mic...@ya...> - 2004-10-16 03:28:14
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Hi Carlos!
I faced the same problem a day ago. This is a bug with Joins, you may
pass a joinMethodName argument to solve this problem in your version,
or update to a newer version from svn. I don't try the newer version,
but, as Andrew Bennetts suggests me, I will try this weekend :)
I hope I helped you, if I don't, you can mail me in portuguese (you are
from python-brasil, aren't you?)...
seeya
--- Carlos Ribeiro <car...@gm...> escreveu:
> Hello all. I'm writing a prototype using sqlobjects and sqlite, and
> I've run into a strange problem. It may be a dumb mistake of mine (as
> I often do :-), but I was not able to spot it. This is the test code:
>
> -----
> from sqlobject import connectionForURI, SQLObject, StringCol, IntCol,
> \
> FloatCol, ForeignKey, MultipleJoin
>
> db = connectionForURI('sqlite:/work/test.db')
>
> class dbWorkItem(SQLObject):
> _connection = db
> wi_name = StringCol(length = 60, notNone = True)
> wi_description = StringCol(length = 200, notNone = True, default
> = '')
> wi_form_class = StringCol(length = 40, notNone = True)
> wi_form_id = IntCol(default=0)
> owner = ForeignKey('dbUser')
> workflow = ForeignKey('dbWorkFlow')
>
> class dbUser(SQLObject):
> _connection = db
> user_nickname = StringCol(length = 15, notNone = True,
> alternateID = True)
> user_password = StringCol(length = 15, notNone = True, default =
> '')
> user_name = StringCol(length = 40, notNone = True, default =
> '')
> user_address1 = StringCol(length = 40, notNone = False, default
> = '')
> user_address2 = StringCol(length = 40, notNone = False, default
> = '')
> user_city = StringCol(length = 40, notNone = False, default
> = '')
> user_comments = StringCol(length = 400, notNone = False, default
> = '')
> workitems = MultipleJoin('dbWorkItem')
>
> def new_db():
> dbUser.createTable()
> dbWorkItem.createTable()
> dbUser(user_nickname="cribeiro", user_name="Carlos Ribeiro")
> dbWorkItem(wi_name='task1', wi_description='Task 1',
> wi_form_class='', workflow=None, owner=1)
> dbWorkItem(wi_name='task2', wi_description='Task 2',
> wi_form_class='', workflow=None, owner=1)
>
> >>> new_db()
> >>> u = dbUser.get(1)
> >>> u
> <dbUser 1 user_address1='' user_password='' user_address2=''
> user_city='' user_name='Carlos Ribeiro' user_nickname='cribeiro'
> user_comments=''>
> >>> u.workitems
> Traceback (most recent call last):
> File "<interactive input>", line 1, in ?
> AttributeError: 'dbUser' object has no attribute 'workitems'
> >>> u.user_name
> 'Carlos Ribeiro'
> >>> wi = dbWorkItem.get(1)
> >>> wi
> <dbWorkItem 1 wi_form_class='' wi_form_id=0 wi_name='Entra nota
> fiscal' workflowID=None ownerID=1 wi_description='Entra nota fiscal'>
> >>> wi.owner
> <dbUser 1 user_address1='' user_password='' user_address2=''
> user_city='' user_name='Carlos Ribeiro' user_nickname='cribeiro'
> user_comments=''>
> >>> wi.owner is u
> True
>
> For some reason, I cant access the dbUser.workitems property. I tried
> the example provided in the documentation (using Person and Address
> entities), and it works. What am I missing here?
>
> --
> Carlos Ribeiro
> Consultoria em Projetos
> blog: http://rascunhosrotos.blogspot.com
> blog: http://pythonnotes.blogspot.com
> mail: car...@gm...
> mail: car...@ya...
>
>
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=====
--
Michel Thadeu Sabchuk
Curitiba/PR
_______________________________________________________
Yahoo! Acesso Grátis - Internet rápida e grátis. Instale o discador agora! http://br.acesso.yahoo.com/
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From: Carlos R. <car...@gm...> - 2004-10-18 12:07:58
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Hello all,
I just update my sqlobject installation, but I'm still having problems
with MultipleJoins. This time the problem seems to be a little easier
to diagnose, given the result of my test session:
>>> execfile('test_sqlobj.py')
>>> new_db()
>>> u = dbUser.get(1)
>>> u
<dbUser 1 user_address1='' user_password='' user_address2=''
user_city='' user_name='Carlos Ribeiro' user_nickname='cribeiro'
user_comments=''>
>>> u.workitems
Traceback (most recent call last):
File "<interactive input>", line 1, in ?
File "<string>", line 1, in <lambda>
File "C:\Python23\Lib\site-packages\sqlobject\joins.py", line 127,
in performJoin
inst.id)
File "C:\Python23\Lib\site-packages\sqlobject\dbconnection.py", line
408, in _SO_selectJoin
return self.queryAll("SELECT %s FROM %s WHERE %s = %s" %
File "C:\Python23\Lib\site-packages\sqlobject\dbconnection.py", line
217, in queryAll
return self._runWithConnection(self._queryAll, s)
File "C:\Python23\Lib\site-packages\sqlobject\dbconnection.py", line
125, in _runWithConnection
val = meth(conn, *args)
File "C:\Python23\Lib\site-packages\sqlobject\dbconnection.py", line
210, in _queryAll
self._executeRetry(conn, c, s)
File "C:\Python23\Lib\site-packages\sqlobject\dbconnection.py", line
196, in _executeRetry
return cursor.execute(query)
File "C:\Python23\Lib\site-packages\sqlite\main.py", line 244, in execute
self.rs = self.con.db.execute(SQL)
DatabaseError: no such column: db_user_id
It seems that the sqlobject code that 'mangles' the column names is
trying to convert the 'uppercase-ID' convention that is used for
automatic primary keys to the 'underscore' convention. I'm not yet
familiar with sqlobject internals, though -- I'll attempt to fix it
myself, but no promises :-)
(btw, it seems that the problem was triggered by my own naming
convention. I'll just rename all entities and see what happens)
The script that defines the database is as follows:
---------------
from sqlobject import connectionForURI, SQLObject, StringCol, IntCol, \
FloatCol, ForeignKey, MultipleJoin
db = connectionForURI('sqlite:/work/test.db')
class dbWorkItem(SQLObject):
_connection = db
wi_name = StringCol(length = 60, notNone = True)
wi_description = StringCol(length = 200, notNone = True, default = '')
wi_form_class = StringCol(length = 40, notNone = True)
wi_form_id = IntCol(default=0)
owner = ForeignKey('dbUser')
workflow = ForeignKey('dbWorkFlow')
class dbUser(SQLObject):
_connection = db
user_nickname = StringCol(length = 15, notNone = True, alternateID = True)
user_password = StringCol(length = 15, notNone = True, default = '')
user_name = StringCol(length = 40, notNone = True, default = '')
user_address1 = StringCol(length = 40, notNone = False, default = '')
user_address2 = StringCol(length = 40, notNone = False, default = '')
user_city = StringCol(length = 40, notNone = False, default = '')
user_comments = StringCol(length = 400, notNone = False, default = '')
workitems = MultipleJoin('dbWorkItem')
def new_db():
dbUser.createTable()
dbWorkItem.createTable()
dbUser(user_nickname="cribeiro", user_name="Carlos Ribeiro")
dbWorkItem(wi_name='task1', wi_description='Task 1',
wi_form_class='', workflow=None, owner=1)
dbWorkItem(wi_name='task2', wi_description='Task 2',
wi_form_class='', workflow=None, owner=1)
--
Carlos Ribeiro
Consultoria em Projetos
blog: http://rascunhosrotos.blogspot.com
blog: http://pythonnotes.blogspot.com
mail: car...@gm...
mail: car...@ya...
|
|
From: Carlos R. <car...@gm...> - 2004-10-18 12:50:55
|
I've found my 'bug', and it hasn't nothing to do with naming conventions. It was a mistake of mine: my one-to-many relationship used a different column name from the default one, and I was not aware that in this case I had to supply a joinedColumn parameter (in fact, another user pointed it out to me, but I misunderstood his point, and assumed that I just had to upgrade my SQLObject installation). Regarding this problem, I have a suggestion: add a remark on the "One-to-Many Relationships" section of the documentation. The relevant information does exist but it's buried down in the MultipleJoin reference; so when I replayed the example provided in the tutorial section it worked, but I was not aware of the option, until I read the reference. For example, something like this: http://www.sqlobject.org/docs/SQLObject.html: """ We get the backreference with addresses = MultipleJoin('Address'). When we access a person's addresses attribute, we will get back a list of all the Address objects associated with that person. An example: p = Person(firstName='John', lastName='Doe') print p.addresses #>> [] a1 = Address(street='123', city='Smallsville', state='IL', zip='50484', person=p) print [a.street for a in p.addresses] #>> ['123'] In this case, the relationship between the 'Person' entity and the 'Address.person' ForeignKey() column is detected and created with no need for any extra information -- the name is mapped automatically. However, if the name of the ForeignKey() column is different from the entity name which it relates with, a joinedColumn argument will be required. For example: <...> """ I found my mistake only after realizing that the join method had no other way to find the joined-to column :-) But it's easy to overlook it, because SQLObject abstracts very well from these 'implementation details'. That's why I believe a comment early in the documentation (or in a FAQ section) could be useful. -- Carlos Ribeiro Consultoria em Projetos blog: http://rascunhosrotos.blogspot.com blog: http://pythonnotes.blogspot.com mail: car...@gm... mail: car...@ya... |
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