I'd like a db(query).select(...) operation to return a set of rows in which
there can only be one instance of a row with a particular value for a
certain field. My query is like this:
book_query = ((db.t_article.f_book_id != None) &
(db.t_article.f_book_id == db.t_book_image.id))
article_image_query = (db.t_article_image.f_article_id ==
db.t_article.id)
query = [stuff pertaining to t_article] & (article_image_query |
book_query)
The idea is to find all t_article entries within a certain time frame
(that's the stuff in brackets, which has been omitted), which either have
an image associated with them, or which reference a t_book entry which has
an image associated with it.
The select statement is like this:
rows = db(query).select(limitby = (0, number_of_records), orderby =
'<random>')
I'd like the select statement to return no more than one row with a
particular value for the f_book_id field. With the above select() statement
as it is, it's possible for rows[0]['t_article']['f_book_id'],
rows[1]['t_article']['f_book_id'], and rows[2]['t_article']['f_book_id'],
for example, to have the same value. Is it possible to modify the above
code so that in situations like the preceding, only one of those rows
(doesn't matter which one) is returned, and assigned to the rows object?
Thanks.
--
Resources:
- http://web2py.com
- http://web2py.com/book (Documentation)
- http://github.com/web2py/web2py (Source code)
- https://code.google.com/p/web2py/issues/list (Report Issues)
---
You received this message because you are subscribed to the Google Groups
"web2py-users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to web2py+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
