question about cx_Oracle .thanks

[coolmenu]

David Fraser <davidf at sjsoft.com> wrote in message news:<cbghcs$5m3$1 at ctb-nnrp2.saix.net>...
> coolmenu wrote:
> > Hi 
> >   i hava a db ORACLE 10G,a table valid_card
> > (card_no,varchar2(10),now_balance number (12,2))
> > 
> >  its'some record in table ('7188','42055.66')
> > 
> >  i use cx_Oracle to select now_balance from table
> >  
> >   curobj.execute("select loan_amount from valid_card where
> > card_no='7181930166881974'");
> > [<NumberVar object at 0x013A6920>]
> > 
> >>>>tuple=curobj.fetchone()
> >>>>tuple
> > 
> > (42505.660000000003)
> > 
> > why 42505.66---->42505.6600000000003???
> > thanks
> 
> This is because of the conversion of the float to decimal. Float objects 
> have limited accuracy. I don't think it's much to do with cx_Oracle
> 
> David


Can someone give me a advice? how can i do?
donnt select number from oracle?