Hi everybody,
in the script reported below mapper.select will fail in presence of
'limit' parameter if the condition is given as literal rather than with
column object and the mapper is a join:
ret = m.select(cities.c.city_name == 'Rome' , limit=10)
#ret = m.select("city_name = 'Rome'" , limit=10) ### FAILS
on the other hand
ret = m.select("user_id > 2", limit=10)
will also work, since the field on which I filter is from the first table
of the join. If I understand this depends on the way limit is implemented.
If I understand correctly the docs, sqlalchemy will try to limit on the
number of instances of the first table while I'd like to limit on the
resulting rowset, is there any way of achieving this?
Thanks in advance
sandro
*:-)
from sqlalchemy import *
#eng = create_engine("sqlite://filename=test-sql.db", echo=False)
eng = create_engine("sqlite://", echo=False)
cities = Table('city', eng,
Column('city_id', Integer, primary_key = True),
Column('city_name', String(30)),
Column('country', String(30), nullable = False)
)
users = Table('users', eng,
Column('user_id', Integer, primary_key = True),
Column('user_name', String(30), nullable = False),
Column('city_id', String(30), ForeignKey("city.city_id"),
nullable = False),
)
users.create()
users.insert().execute(
{'user_id': 1 , 'user_name': 'Sam', 'city_id' : '1' },
{'user_id': 2 , 'user_name': 'Sid', 'city_id' : '1' },
{'user_id': 3 , 'user_name': 'Axe', 'city_id' : '2' },
{'user_id': 4 , 'user_name': 'Ted', 'city_id' : '2' })
cities.create()
cities.insert().execute(
{'city_id': 1, 'city_name': 'Rome', 'country': 'Italy'},
{'city_id': 2, 'city_name': 'Paris', 'country': 'France'},
)
class User(object): pass
class City(object): pass
c2 = mapper(City, cities)
rel2 = relation(c2, lazy=False, )
m = mapper(User, users, properties = { 'cities' : rel2 } )
ret = m.select("user_id > 2", limit=10)
ret = m.select(cities.c.city_name == 'Rome' , limit=10)
#ret = m.select("city_name = 'Rome'" , limit=10)
ret = m.select("city_name = :city_name" , params={'city_name' : 'Rome'})
--
Sandro Dentella *:-)
e-mail: [EMAIL PROTECTED]
http://www.tksql.org TkSQL Home page - My GPL work
-------------------------------------------------------
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642
_______________________________________________
Sqlalchemy-users mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/sqlalchemy-users
