Interested in these? Handy for paging through stuff you've already pulled from the db (otherwise limitby is best):
rows = db().select(db.things.ALL) skip - bypass the specified number of elements and return the rest take - return the specified number of elements from the beginning >page = rows.skip(pagenum * pagesize).take((pagesize+1) On Oct 28, 12:50 pm, mdipierro <[email protected]> wrote: > deal! uploading. > > On Oct 28, 12:42 pm, Alex Fanjul <[email protected]> wrote: > > > I agree with Jonathan, (find) and (exclude) are the best. > > Filter is like "let me this in the result" (just the opposite sense), > > and remove is like "real remove this from my database" > > > So... '*Find*' this in my rows, BUT also *Exclude *this from my results! > > > Alex F > > > El 28/10/2009 18:23, Jonathan Lundell escribió: > > > > On Oct 28, 2009, at 9:58 AM, mdipierro wrote: > > > >> On a third thougth. Mr Freeze original names are better (find and > > >> filter it is). > > > > Your use of 'filter' (or my confusion about it) for both cases > > > illustrates its ambiguity. How about 'find' and 'exclude'? > > > >> I added slices too. Here is an example: > > > >> b=DAL('sqlite://storage') > > >> db.define_table('a',Field('b')) > > >> db.a.insert(b='aaa') > > >> db.a.insert(b='aab') > > >> db.a.insert(b='abb') > > >> db.a.insert(b='bbb') > > > >> ### return rows that match condition > > >> rows=db(db.a.id>0).select().find(lambda row: row.b>0) > > > >> #### sort rows > > >> rows0 = rows.sort(lambda row: row.b.upper()): > > > >> rows1=db(db.a.id>0).select() > > >> ### move matching rows from rows1 to rows2 > > >> rows2=rows1.filter(lambda row: row.b>'b') > > > >> ### get a slice of the rows > > >> rows3=rows[1:3] > > > >> They can be mixed and matched > > > >> rows=(rows1|rows2|rows3).find(..)[:].filter(..).sort(..) > > > >> Now one implement at DAL level most functions missing on GAE like OR, > > >> LIKE, BELONGS. > > > >> Massimo > > > >> On Oct 28, 11:17 am, mdipierro<[email protected]> wrote: > > > >>> Ok, I am going with filter (same as your find) and extract (same as > > >>> your filter with some changes to make it faster and issue that caused > > >>> it to skip some rows). In trunk now. > > > >>> Massimo > > > >>> On Oct 28, 10:51 am, "mr.freeze"<[email protected]> wrote: > > > >>>> Now I'm confused :) What if you just changed the 'where' to 'find' > > >>>> and kept both. Filter should reduce the actual set, returning the > > >>>> removed rows. Find should just return the matched rows. > > > >>>> On Oct 28, 10:15 am, mdipierro<[email protected]> wrote: > > > >>>>> OK I just put the where function in trunk but renamed it filter > > >>>>> (sorry > > >>>>> for the confusion). > > > >>>>> On Oct 28, 10:11 am, Joe Barnhart<[email protected]> wrote: > > > >>>>>> I know, that's what I'm saying.... the word "where" suggests it > > >>>>>> is an SQL > > >>>>>> verb but it has nothing to do with SQL. I was just thinking it > > >>>>>> might be > > >>>>>> confusing to new users of w2p. > > > >>>>>> On Wed, Oct 28, 2009 at 6:32 AM, mr.freeze > > >>>>>> <[email protected]> wrote: > > > >>>>>>> No, anything post 'select' is done after the db call, including > > >>>>>>> first > > >>>>>>> () and last(). > > > >>>>>>> On Oct 28, 2:51 am, Joe Barnhart<[email protected]> wrote: > > > >>>>>>>> I love the functionality, but doesn't calling the function > > >>>>>>>> "where" > > >>>>>>>> conjure up the SQL WHERE clause? I might think it was doing > > >>>>>>>> something > > >>>>>>>> with SELECT...WHERE in the underlying DB. > > > >>>>>>>> -- Joe B. > > > >>>>>>>> On Oct 27, 10:11 pm, "mr.freeze"<[email protected]> wrote: > > > >>>>>>>>> Works! Would you be interested in these for sql.py Rows class?: > > > >>>>>>>>> def where(self,f): > > >>>>>>>>> if not self.response: > > >>>>>>>>> return None > > >>>>>>>>> rows = [] > > >>>>>>>>> for i in range(0,len(self)): > > >>>>>>>>> row = self[i] > > >>>>>>>>> if f(row): rows.append(self.response[i]) > > >>>>>>>>> return Rows(self._db,rows,*self.colnames) > > > >>>>>>>>> def filter(self,f): > > >>>>>>>>> if not self.response: > > >>>>>>>>> return None > > >>>>>>>>> rows = self.response > > >>>>>>>>> removed = [] > > >>>>>>>>> for i in range(0,len(self)): > > >>>>>>>>> row = self[i] > > >>>>>>>>> if f(row): > > >>>>>>>>> removed.append(rows[i]) > > >>>>>>>>> rows.remove(rows[i]) > > >>>>>>>>> return Rows(self._db,removed,*self.colnames) > > > >>>>>>>>> Example: > > >>>>>>>>> db.define_table('things',Field('category')) > > >>>>>>>>> rows = db(db.things.id>0).select() > > >>>>>>>>> tests = rows.where(lamdba row: row.category=="test") # > > >>>>>>>>> returns matches > > >>>>>>>>> rows.filter(lamdba row: row.category=="test")# removes and > > >>>>>>>>> returns > > >>>>>>>>> removed > > > >>>>>>>>> On Oct 27, 10:49 pm, mdipierro<[email protected]> wrote: > > > >>>>>>>>>> Thanks. Just fixed in trunk! > > > >>>>>>>>>> On Oct 27, 10:35 pm, "mr.freeze"<[email protected]> wrote: > > > >>>>>>>>>>> I get a syntax error when using this. I believe line 2926 of > > >>>>>>>>>>> Rows.__getitem__ needs to be changed from: > > > >>>>>>>>>>> if i>= len(self.response) or i< 0: > > > >>>>>>>>>>> ...to... > > > >>>>>>>>>>> if i>= len(self.response): > > > >>>>>>>>>>> since Rows.last() returns self[-1] > > > -- > > Alejandro Fanjul Fdez. > > [email protected] --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py-users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/web2py?hl=en -~----------~----~----~----~------~----~------~--~---
