set variable on models or modules

[黄祥]

is there any difference to set variable on models or modules ?

e.g.

models/db_connect.py

db = DAL('sqlite://test.sqlite', pool_size = 1)

modules/db_connect.py

from gluon.dal import DAL
from gluon import current
db = DAL('sqlite://test.sqlite', pool_size = 1)
cache = current.cache
cache_time_expire = 10
cache_model = cache.ram # cache.ram, cache.disk, cache.memcache, cache.redis
cache_db = (cache_model, cache_time_expire)

controllers/install.py

import db_connect
def index():
    db = db_connect.db
    db_schema_1_address.define(db = db)
    address_id_1 = db.address.insert(street = 'a', zip_code = '1', city = 'a', country = 'a')

controllers/api.py

import db_connect
#db = db_connect.db # not worked, must use from models/db.py
cache_db = db_connect.cache_db # this variable can be used from modules, no error occured
db_schema_1_address.define(db = db)

def response_json_rows():
    if not request.env.request_method == 'GET': raise HTTP(403)
    table_name = request.args(0)
    id = request.args(1)
    if id.isdigit() and int(id) > 0:
        query = (db[table_name]['id'] == id)
    else:
        query = (db[table_name]['id'] > 0)
    rows = db(query).select(orderby = ~db[table_name]['id'],
                            cache = cache_db,
                            cacheable = True)
    return response.json(rows)

Traceback (most recent call last):
  File "/Users/sugizo/learn/python/web2py/gluon/restricted.py", line 219, in restricted
    exec(ccode, environment)
  File "/Users/sugizo/learn/python/web2py/applications/test/controllers/api.py", line 24, in <module>
    db_schema_1_address.define(db = db)
  File "applications/test/modules/db_schema_1_address.py", line 64, in define
    format = lambda r: \
  File "/Users/sugizo/learn/python/web2py/gluon/packages/dal/pydal/base.py", line 581, in define_table
    raise SyntaxError('table already defined: %s' % tablename)
SyntaxError: table already defined: address

any ideas ?

intention is to move define tables from models into modules and load it on controller when it's required, with minimal effort

thx n best regards,

stifan

[Val K]

It seems  that defining db=DAL(...) at module level is not  a good idea  

http://www.web2py.com/books/default/chapter/29/04/the-core#Accessing-the-API-from-Python-modules