[Tutor] Setting up a database

[Liam Clarke]

While we generally don't get too specific with assignments and/or homework - 

For a traditional database, you'd have to go the mySQL route. A
dictionary is good, but for only one discreet key. That said, you
could do it with objects like this -

dictOfTransactionObjects = {}

class CashTransaction:
         def __init__(self, amount, depOrWith):
               self.amount=float(amount)
               self.transactionType = depOrWith
    
        
#...do various things which get the various values dateStamp, amount, transType

dictOfTransactionObjects[dateStamp] = CashTransaction(amount, transType)


So, now your dictionary will be {'01/05/2004-22:00:00' : <instance of
CashTransaction>}

And you could search either by the dictionary key which is acting like
a primary key,  (the timestamp) or like this -


isWith = []
for  (key, item) in dictOfTransactionObjects.items():
       if item.transactionType == 'Withdrawal':
          isWith.append(key)


And isWith becomes a list of primary keys of withdrawals.
That said, I would use SQL queries instead, it's a lot more
straightforward, you'll end up reinventing several wheels this way.


Regards, 

Liam Clarke




On Tue, 01 Mar 2005 18:22:08 -0500, James O. Sweeney
<james.sweeney at ieee.org> wrote:
>  
>  
> 
> Hello, 
> 
> I have an assignment that entails entering cash transactions as records. The
> significant record fields are a date/time stamp, the amount, and whether the
> transaction is a deposit or withdrawal. My question is about setting up the
> database file. In Python there is a dictionary function but it looks as if
> only one value can be assigned to the key (I intend to make the key the
> timestamp). The file has to be searchable so that reports can be pulled
> regarding amount, date range, etc. – the usual things one would do with a
> database. I can't figure if I can make a query on a multi-field record in
> Python without engaging a dependency such a storing the record in a mySQL
> database and querying it from Python. I'm having real burnout with this and
> would appreciate a point in the right direction. 
> 
> Much Thanks, 
> 
> James 
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> 
> 
> 


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