A couple other notes: - I know I could start with a query that will return everything, like "db.person.id > 0", but I'm worried about how that will interact with queries that are optimized by an index that doesn't include the id column
- An old trick when building up SQL WHERE statements as strings is to start with "WHERE 1=1" (which should get optimized away by the SQL engine) and go from there. However, I couldn't find a way to make a Query that evaluated to the equivalent of "1=1". Cheers, Kevin On Oct 5, 1:39 pm, Kevin Ivarsen <kivar...@gmail.com> wrote: > Hi everybody, > > I'm building a page that will search for rows in a database table > based on optional URL parameters, or return all rows if no parameters > are given. However, I'm having trouble finding a good way to build up > the query without having an existing Query object to start with. > Web2py currently lets me do something like this: > > q = (db.person.height > 5) > q = q & (db.person.height < 6) > db(q).select() > > But I'd like to be able to do something like this (in pseudocode): > > q = EmptyQuery(defaultTable=db.person) > if request.vars.minheight: > q = q & (db.person.height > request.vars.minheight) > if request.vars.maxheight: > q = q & (db.person.height < request.vars.maxheight) > > people = db(q).select() > > so that if no parameters are given, it will select all from db.person, > but you can optionally filter by min and max height. > > Is there an easy way to do this in web2py? > > Thanks! > Kevin
