can i set up a mysql db connection as a class ?

[Winfried Tilanus]

On 04/28/2006 07:54 AM, *binarystar* wrote:

Just wondering: is there any risk of two threads accessing the Execute
function at the same time and getting something like this on the same
cursor object:

thread_1: self.cursor.Execute( sql_statement )
thread_2: self.cursor.Execute( sql_statement )
thread_1: return self.cursor.FetchAll()
thread_2: return self.cursor.FetchAll()

In that case the queries would seriously be messed up. My intuition says
this would need some locking or a 'cursor-pool'.

best wishes,

Winfried


> your on the right track ... create something like this ( hope the
> formatting doesn't go to hay wire )
> 
> class DB_Connector(object):
> 
>     """ Humble Database Connection Class """
>         def __init__(self, host="localhost",
> user="MyUser",passwd="MyPassword", **other_db_arguments):
>                       self.host   =   host
>            self.user   =   user
>            self.passwd =   passwd
>                       # Unpack Other Database Arguments Here
>                                  self.CreateConnection()
>                def CreateConnection( self ):
>               self.cursor = MySQLdb.connect(self.host, self.user,
> self.passwd)
>            def DestroyConnection( self ):
>               self.cursor.close()
>            def Execute( self, sql_statement ):
>               self.cursor.Execute( sql_statement )
>               return self.cursor.FetchAll()
>        Then when you run your program create an instance of the object
> 
> db_connection     = DB_Connector( 'localhost', 'administrator',
> 'betelgeuse99', auto_commit=1, other_keyword_arg="yes" )
> 
> now when you pass the db_connection instance to other classes, a copy
> will be made automagically
> 
> thread_1_instance    = ThreadingClass( db_connection )
> thread_2_instance    = ThreadingClass( db_connection )
> thread_3_instance    = ThreadingClass( db_connection )
> 
> should work ..
> I hope this is useful