Thread: [SQLObject] Multiple relations between two tables
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From: Andy T. <an...@ha...> - 2003-07-30 12:37:07
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Hi,
How do I define two (or more) relationships between two tables in my
schema? I have a currencies table and a currency_rates table. Before I
try and add the relationships their definitions are;
"""
class Currencies(SQLObject):
currencyCode=StringCol(length=6)
currencyDesc=StringCol(length=255)
exchanges=MultipleJoin('Exchanges', joinColumn='currency_id')
countries=MultipleJoin('Countries', joinColumn='currency_id')
class CurrencyRates(SQLObject):
rateDate=DateTimeCol()
rate=Col()
"""
Now I get confused when I add the two relationships (currency from and
currency to). I tried;
"""
class Currencies(SQLObject):
currencyCode=StringCol(length=6)
currencyDesc=StringCol(length=255)
exchanges=MultipleJoin('Exchanges', joinColumn='currency_id')
countries=MultipleJoin('Countries', joinColumn='currency_id')
ratesFrom=MultipleJoin('CurrencyRates', joinColumn='currency_from_id')
ratesTo=MultipleJoin('CurrencyRates', joinColumn='currency_to_id')
class CurrencyRates(SQLObject):
rateDate=DateTimeCol()
rate=Col()
currencyFrom=ForeignKey('Currencies')
currencyTo=ForeignKey('Currencies')
"""
But this causes an error on import;
"""
Traceback (most recent call last):
File "classes.py", line 51, in ?
class CurrencyRates(SQLObject):
File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
line 233, in __new__
newClass.addColumn(column)
File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
line 503, in addColumn
'_SO_class_%s' % column.foreignKey)
File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
line 102, in addNeedSet
getattr(obj, attr)(cls)
File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
line 404, in __new__
val._init(id, connection, selectResults)
File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
line 662, in _init
selectResults = (connection or
self._connection)._SO_selectOne(self, dbNames)
File
"C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\DBConnection.py", line
267, in _SO_selectOne
return self.queryOne("SELECT %s FROM %s WHERE %s = %s" %
File
"C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLBuilder.py", line
126, in sqlRepr
raise ValueError, "Unknown SQL builtin type: %s for %s" % \
ValueError: Unknown SQL builtin type: <class
'SQLObject.SQLObject.MetaSQLObject'> for <class '__main__.Currencies'>
"""
Any suggestions? Apologies if this question has already been answered.
Regards,
Andy
--
--------------------------------------------------------------------------------
From the desk of Andrew J Todd esq - http://www.halfcooked.com/
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From: Ian B. <ia...@co...> - 2003-08-01 02:09:15
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This is the same bug that Javier was encountering. There's a fix in
CVS, or if SF CVS is slow (which it has been) and you want immediate
satisfaction, use this replacement function in SQLObject.py:
def addNeedSet(obj, setCls, registry, attr):
try:
cls = findClass(setCls, registry=registry)
if callable(getattr(obj, attr, None)):
if not isinstance(getattr(obj, attr), type):
# Otherwise we got a class, which means we probably
# already set this column.
getattr(obj, attr)(cls)
else:
setattr(obj, attr, cls)
return
except KeyError:
pass
q = needSet.setdefault(registry, {}).setdefault(setCls, [])
q.append((obj, attr))
On Wed, 2003-07-30 at 07:17, Andy Todd wrote:
> Hi,
>
> How do I define two (or more) relationships between two tables in my
> schema? I have a currencies table and a currency_rates table. Before I
> try and add the relationships their definitions are;
>
> """
> class Currencies(SQLObject):
> currencyCode=StringCol(length=6)
> currencyDesc=StringCol(length=255)
> exchanges=MultipleJoin('Exchanges', joinColumn='currency_id')
> countries=MultipleJoin('Countries', joinColumn='currency_id')
>
> class CurrencyRates(SQLObject):
> rateDate=DateTimeCol()
> rate=Col()
> """
>
> Now I get confused when I add the two relationships (currency from and
> currency to). I tried;
>
> """
> class Currencies(SQLObject):
> currencyCode=StringCol(length=6)
> currencyDesc=StringCol(length=255)
> exchanges=MultipleJoin('Exchanges', joinColumn='currency_id')
> countries=MultipleJoin('Countries', joinColumn='currency_id')
> ratesFrom=MultipleJoin('CurrencyRates', joinColumn='currency_from_id')
> ratesTo=MultipleJoin('CurrencyRates', joinColumn='currency_to_id')
>
> class CurrencyRates(SQLObject):
> rateDate=DateTimeCol()
> rate=Col()
> currencyFrom=ForeignKey('Currencies')
> currencyTo=ForeignKey('Currencies')
> """
>
> But this causes an error on import;
>
> """
> Traceback (most recent call last):
> File "classes.py", line 51, in ?
> class CurrencyRates(SQLObject):
> File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
> line 233, in __new__
> newClass.addColumn(column)
> File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
> line 503, in addColumn
> '_SO_class_%s' % column.foreignKey)
> File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
> line 102, in addNeedSet
> getattr(obj, attr)(cls)
> File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
> line 404, in __new__
> val._init(id, connection, selectResults)
> File "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLObject.py",
> line 662, in _init
> selectResults = (connection or
> self._connection)._SO_selectOne(self, dbNames)
> File
> "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\DBConnection.py", line
> 267, in _SO_selectOne
> return self.queryOne("SELECT %s FROM %s WHERE %s = %s" %
> File
> "C:\PROGRA~2\PYTHON22\Lib\site-packages\SQLObject\SQLBuilder.py", line
> 126, in sqlRepr
> raise ValueError, "Unknown SQL builtin type: %s for %s" % \
> ValueError: Unknown SQL builtin type: <class
> 'SQLObject.SQLObject.MetaSQLObject'> for <class '__main__.Currencies'>
> """
>
> Any suggestions? Apologies if this question has already been answered.
>
> Regards,
> Andy
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From: Andy T. <an...@ha...> - 2003-08-01 13:22:56
|
Ian Bicking wrote:
> This is the same bug that Javier was encountering. There's a fix in
> CVS, or if SF CVS is slow (which it has been) and you want immediate
> satisfaction, use this replacement function in SQLObject.py:
>
> def addNeedSet(obj, setCls, registry, attr):
> try:
> cls = findClass(setCls, registry=registry)
> if callable(getattr(obj, attr, None)):
> if not isinstance(getattr(obj, attr), type):
> # Otherwise we got a class, which means we probably
> # already set this column.
> getattr(obj, attr)(cls)
> else:
> setattr(obj, attr, cls)
> return
> except KeyError:
> pass
> q = needSet.setdefault(registry, {}).setdefault(setCls, [])
> q.append((obj, attr))
>
>
>
> On Wed, 2003-07-30 at 07:17, Andy Todd wrote:
>
>>Hi,
>>
>>How do I define two (or more) relationships between two tables in my
>>schema? I have a currencies table and a currency_rates table. Before I
>>try and add the relationships their definitions are;
>>
[snip]
>>
Thanks Ian, works like a charm. And thanks for SQLObject too, its a gem.
Regards,
Andy
--
--------------------------------------------------------------------------------
From the desk of Andrew J Todd esq - http://www.halfcooked.com/
|
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