[web2py] Bug? The DAL gives different SQL when query is provided as string.

[Limedrop]

I've copied this from the bottom of another thread.


The DAL gives different SQL when a query is provided in string format.
Is this a bug, or should I not expect this to work?


See the example below, the first SQL works, the second SQL raises an
error.


>>>from gluon.dal import Query
>>>query = (db.comment.id > 0) & (db.webpage.title == 'FAQ') & 
>>>(db.comment.page_id == db.webpage.id)
>>>query_as_string = str(query)
>>>query_from_string = Query(db, query_as_string)
>>>print db(query)._select(db.comment.body)

SELECT  comment.body FROM comment, webpage WHERE (((comment.id > 0)
AND (webpage.title = 'FAQ')) AND (comment.page_id = webpage.id));


>>>print db(query_from_string)._select(db.comment.body)

SELECT  comment.body FROM comment WHERE ((((comment.id > 0) AND
(webpage.title = 'FAQ')) AND (comment.page_id = webpage.id)));



Why do this?  If the were possible it would enable you to easily save
a query in the session.  For example:

==Controller 1==
query1 = (db.comment.id > 0) & (db.webpage.title == 'FAQ') &
(db.comment.page_id == db.webpage.id)
session.query = str(query1)

==Controller 2==
from gluon.dal import Query
query2 = Query(db, session.query)


This does NOT work because the DAL gives different SQL for query1 and
query2.