[Tutor] The case of the missing close

[Kent Johnson]

Here is a sketch to get you started. I'm not sure how cursors work so I may be off the mark! You may 
want to keep the cursor as an attribute of db so you can reuse it?

class db:
   def __init__(self, db, uname, passwd)
     self.connection = cx_Oracle.connect(dsn=db,user=uname,password=passwd)

   def execute(self, sql):
     cursor = connection.cursor()
     cursor.execute(sql)
     return cursor

   def close(self):
     self.connection.close()
     self.connection = None # Prevent reusing a closed connection


Your client code would look like this:

import db_utils

dbobj = db_utils.db('test_d','FOO','foo')

cursobj = dbobj.execute('SELECT userid, name, role, desk_phone, pager FROM
contacts')

results=cursobj.fetchall()

for row in results:
     print row

dbobj.close()


Kent

Robert, Andrew wrote:
> Hi Kent,
> 
> I tried returning the connection but that didn't work either.
> 
> In fact, returning the connection fails to create the cursor object in the calling program and the whole program dies a miserable death.
> 
> I am intrigued about the idea of a class though.
> 
> I've never really had the need to use them before now but it seems like now is a good time to start.
> 
> I'll let you know how things work out.
> 
> 
> 
> -----Original Message-----
> From: tutor-bounces at python.org on behalf of Kent Johnson
> Sent: Tue 11/30/2004 10:21 PM
> Cc: tutor at python.org
> Subject: Re: [Tutor] The case of the missing close
>  
> I don't know cx_Oracle, but my guess is you want to close the actual connection object, not the 
> cursor. Your dbopen() function doesn't expose the connection.
> 
> One option would be to return the connection rather than the cursor. Then clients could close the 
> connection when done. Another option is to create a class that holds both the connection and the 
> cursor, then you can have close() on the class actually close the connection.
> 
> Kent
> 
> 
> "MFS Relay Service" made the following
>  annotations on 12/01/2004 05:15:44 AM
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