[SQLObject] Multiple relations between two tables

[Andy T. <an...@ha...>]

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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