Has anyone tried the "zig-zag" merge join algorithm that Google uses to do something similar with their AppEngine data store (BigTable)? It's described here starting on slide 29: http://www.scribd.com/doc/16952419/Building-scalable-complex-apps-on-App-Engine
<http://www.scribd.com/doc/16952419/Building-scalable-complex-apps-on-App-Engine>It seems like you could use this technique across multiple tables to perform equality tests without building additional indices. Jesse On Fri, Mar 11, 2011 at 9:54 PM, Stack <st...@duboce.net> wrote: > Understand the ROWCOL can use more memory than ROWs. In general, > blooms could soak up a bunch of your RAM. Just be conscious of this > fact. > St.Ack > > On Fri, Mar 11, 2011 at 4:25 PM, Usman Waheed <usm...@opera.com> wrote: > > I suggest it to be ROWCOL because you have many columns to match against > in > > your second table (column qualifiers). > > > > -Usman > > > >> Should the Bloom filter be ROW or ROWCOL? > >> > >> Vishal > >> > >> On Fri, Mar 11, 2011 at 11:44 AM, Lars George <lars.geo...@gmail.com> > >> wrote: > >> > >>> Hi, > >>> > >>> If you expect a lot of misses with that approach then enable bloom > >>> filters > >>> on the second table for fast lookups of misses. > >>> > >>> Lars > >>> > >>> On Mar 11, 2011, at 9:44, Amandeep Khurana <ama...@gmail.com> wrote: > >>> > >>> > You can scan through one table and see if the other one has those > >>> > rowids > >>> or > >>> > not. > >>> > > >>> > On Thu, Mar 10, 2011 at 8:08 PM, Vishal Kapoor > >>> > <vishal.kapoor...@gmail.com>wrote: > >>> > > >>> >> Friends, > >>> >> how do I best achieve intersection of sets of row ids > >>> >> suppose I have two tables with similar row ids > >>> >> how can I get the row ids present in one and not in the other? > >>> >> does things get better if I have row ids as values in some > qualifier/ > >>> >> qualifier itself? > >>> >> I hope the question is not too confusing... > >>> >> > >>> >> intersection of {1, 2, 3} and {2, 3, 4} is {2, 3}. > >>> >> while {1,2,3} are row ids from a table, {2,3,4} may come from other > >>> table > >>> >> as > >>> >> qualifiers in some row. > >>> >> > >>> >> thanks, > >>> >> Vishal > >>> >> > >>> > > > > > > -- > > Using Opera's revolutionary email client: http://www.opera.com/mail/ > > >
