no. you cannot pickle a database connection.
On Jan 12, 9:04 am, Phyo Arkar <[email protected]> wrote: > I think what i am trying to do is pickling db object. > This will never work , right? > > On Thu, Jan 12, 2012 at 9:10 PM, Phyo Arkar <[email protected]>wrote: > > > > > > > > > Hello Web2py , happy new year! > > > I am trying to use DAL outside in a script file , here is the code : > > > def generate_dbs(db_name,db_path): > > #casesdb = DAL( 'mysql://root@localhost/' + db_name, folder = db_path > > ) > > #casesdb.define_table( 'email_data', migrate = True, *email_halfschema > > ) > > #casesdb.define_table( 'loosefile_data', migrate = True, > > *file_halfschema ) > > #casesdb.define_table( 'attach_data', migrate = True, *file_halfschema > > ) > > #casesdb.define_table( 'meta_data', migrate = True, *metadatas_schema ) > > #return casesdb > > casesdb = DAL('mysql://root@localhost/' + db_name, folder = db_path) > > casesdb.define_table('files_data', migrate = False, *files_schema) > > casesdb.define_table('files_meta_data', migrate = False, > > *files_meta_schema) > > casesdb.define_table('email_meta_data', migrate = False, > > *email_meta_schema) > > return casesdb > > > def pooler(fpath, db_name, db_path, processes=4): > > lst = recursive_flist(fpath) > > print lst > > databases = [generate_dbs(db_name,db_path) for i in range(1,processes)] > > print databases > > processor_pool = Pool(processes=processes) > > print "Pooling Ready" > > matcher_db_lst =list(enumerate(zip(lst,cycle(databases)))) > > #this gets something like this > > [1,["path1",dbcon1],2,["path2",dbcon2],...,21,["path21",dbcon1]] > > return processor_pool.map(generated_edoc_pooling ,matcher_db_lst) > > > Here is the error : > > > Exception in thread Thread-2: > > Traceback (most recent call last): > > File "/usr/lib64/python2.7/threading.py", line 552, in __bootstrap_inner > > self.run() > > File "/usr/lib64/python2.7/threading.py", line 505, in run > > self.__target(*self.__args, **self.__kwargs) > > File "/usr/lib64/python2.7/multiprocessing/pool.py", line 313, in > > _handle_tasks > > put(task) > > PicklingError: Can't pickle <type 'NoneType'>: attribute lookup > > __builtin__.NoneType failed > > > The problem is that , there are too many Nones in DAL's database object > > and cant be seralized into pickle. how can i solve this? > > What i want is to pool only 4 db connections however large the list is. > > > Thanks > > > Phyo.
