in trunk. please check.
On May 5, 8:48 am, Christophe Plat <[email protected]> wrote: > Hello again, > > the above fix breaks delete when items is already a list (such as when > deleting a single entity). The correct fix would therefore be: > > def delete(self): > self._db['_lastsql'] = 'DELETE WHERE %s' % self.where > (items, tablename, fields) = self._select() > tableobj = self._db[tablename]._tableobj > counter = self.items_count(items) > if not isinstance(items,list): > leftitems = items.fetch(1000) > while len(leftitems): > gae.delete(leftitems) > leftitems = items.fetch(1000) > else: > gae.delete(items) > return counter > > Christophe > > On May 5, 1:02 am, Christophe Plat <[email protected]> wrote: > > > Hi Massimo, > > > the issue is that delete can't work directly on the > > google.appengine.ext.db.Query object. In the delete function, items is > > an instance of that Query object, and has to be transformed into a > > list of google.appengine.ext.db.Models - which is what the fetch > > function does. > > In fact, it doesn't have to be limited to 1000: the fetch function > > takes an argument that can have any value - the example said 1000, > > but any other value would be valid. > > > After playing around a bit, I reconsidered the fix to be: > > > def delete(self): > > self._db['_lastsql'] = 'DELETE WHERE %s' % self.where > > (items, tablename, fields) = self._select() > > tableobj = self._db[tablename]._tableobj > > counter = self.items_count(items) > > leftitems = items.fetch(1000) > > while len(leftitems): > > gae.delete(leftitems) > > leftitems = items.fetch(1000) > > return counter > > > so that it removes items by 1000 increments. That should do the trick > > for now, but I see room for performance improvement: > > > - allow the select function to retrieve keys only instead of the > > entire entity, as the documentation explains that it's a lot faster > > (and we don't need the full entity for a delete) > > > - counter = self.items_count(items) could be computed via > > len(leftitems) and the 1000 increments > > > Christophe > > > On May 5, 12:10 am, mdipierro <[email protected]> wrote: > > > > Thank you for reporting this. Please check my fix in trunk. > > > > Massimo > > > > On May 4, 4:16 pm, Christophe Plat <[email protected]> wrote: > > > > > This issue on web2py is related to GAE issue 3119 (http:// > > > > code.google.com/p/googleappengine/issues/detail?id=3119). > > > > I'm using web2py 1.77.3. > > > > > In gql.py, line 702 to 709: > > > > > def delete(self): > > > > self._db['_lastsql'] = 'DELETE WHERE %s' % self.where > > > > (items, tablename, fields) = self._select() > > > > tableobj = self._db[tablename]._tableobj > > > > counter = self.items_count(items) > > > > if counter: > > > > gae.delete(items) > > > > return counter > > > > > According to comment 8 on issue 3119, the delete function no longer > > > > works on Query object, which items is an instance of. It suggests to > > > > change the code to either: > > > > > db.delete(<query>.fetch(1000)) > > > > > or > > > > > db.delete(list(<query>)) > > > > > with a preference to fetch(1000). In other words: a fix for this issue > > > > is to update line 708 to: > > > > > gae.delete(items.fetch(1000)) > > > > > It leaves open the issue of queries returning more than 1000 results, > > > > though. > > > > > Best regards, > > > > Christophe
