Aha! Found and fixed some bugs in my apsw wrapper for stuff that I do not do
often (such as using * to retrieve duplicate column names as I typically always
use AS to name columns explicitly, so the Row was being built with duplicate
names). Also, removed the code that disabled the long_column_names support as
it does not actually require changes to the APSW base, those only being
required if I want to fetch the underlying column metadata).
from __future__ import absolute_import, division, print_function,
unicode_literals
import newapsw
import apsw
db = apsw.Connection('')
db.execute('''
create table addresses( id, name );
create table users( id, address_id, name );
create table pets(id, user_id, name );
insert into addresses(id,name) values ( 1, 'there' );
insert into users(id,address_id,name) values ( 1, 1, 'bob' );
insert into pets(id,user_id,name) values ( 1,1, 'odif' );
''')
cr1 = db.execute('''
select *
from users user
join addresses address
on address.id=user.address_id
join pets pet
on pet.user_id=user.id;
''')
print(1, cr1.fetchone())
cr2 = db.execute('''
select address.id AS address_id,
address.name AS address_name,
user.id AS user_id,
user.address_id AS user_address_id,
user.name AS user_name,
pet.id AS pet_id,
pet.user_id AS pet_user_id,
pet.name AS pet_name
from users AS user
join addresses AS address
on address.id == user.address_id
join pets AS pet
on pet.user_id == user.id;
''')
print(2, cr2.fetchone())
db.execute('''
pragma full_column_names=1;
pragma short_column_names=0;
''')
cr3 = db.execute('''
select *
from users user
join addresses address
on address.id=user.address_id
join pets pet
on pet.user_id=user.id;
''')
print(3, cr3.fetchone())
>py -3 sample.py
1 Row(id=1, address_id=1, name='bob', id_1=1, name_1='there', id_2=1,
user_id=1, name_2='odif')
2 Row(address_id=1, address_name='there', user_id=1, user_address_id=1,
user_name='bob', pet_id=1, pet_user_id=1, pet_name='odif')
3 Row(user_id=1, user_address_id=1, user_name='bob', address_id=1,
address_name='there', pet_id=1, pet_user_id=1, pet_name='odif')
Note:
db.execute => db.cursor().execute
The Row object is just built by an exehook and a rowhook getting the column
names from the cursor.description and mangling them somewhat so that the Row
has distinct names in its list of column names so that the column name can be
accessed as an attribute of the Row ...
If you want to see how it all works get http://www.dessus.com/files/<name>
where <name> is one of apsw-monolith27-gcc32.zip, apsw-monolith36-gcc64.zip,
apsw-monolith37-gcc64.zip. The python code is the same in all of them, just
the compiled apsw pyd is different. import newapsw to activate all the stuff,
then import apsw will have it all in the normal apsw library (the newapsw
module is substituted for the apsw module name in sys.modules).
--
The fact that there's a Highway to Hell but only a Stairway to Heaven says a
lot about anticipated traffic volume.
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