This discussion reminds me that a friend and I discussed the possibility of adding pluggable OpVisitors to allow chained rewrites of the query before execution.
On Wed, Aug 28, 2013 at 10:23 PM, Claude Warren <[email protected]> wrote: > When I did the work on the query engine described above I used an > OpVisitor implementation in modifyOp to rewrite the query. It should be > possible to implement the optimization there, but I don't know that it is > the best place. > > Claude > > > On Wed, Aug 28, 2013 at 5:19 PM, Diogo FC Patrao <[email protected]>wrote: > >> Hi Claude >> >> I meant the first option, optimize queries to run at federated >> environments. Although I'm working on a query "federator" as well, and am >> also interested in similar projects as well. >> >> Thanks >> >> -- >> diogo patrão >> >> >> >> >> On Wed, Aug 28, 2013 at 12:50 PM, Claude Warren <[email protected]> wrote: >> >> > I did some work on query planning for federated queries when I worked >> for >> > DERI. (http://deri.ie). However, that work may have been a bit more >> > complex than you are considering as we had some sources for vocabulary >> > equivalence and were attempting to handle that at the same time. >> > >> > When you say a query planner for federated queries, are you looking to >> > optimise queries that contain federated queries, or attempting to build >> a >> > federated query from a non-federated one? >> > >> > Claude >> > >> > >> > On Wed, Aug 28, 2013 at 1:54 PM, Diogo FC Patrao <[email protected] >> > >wrote: >> > >> > > Hello >> > > >> > > I was thinking about writing a query planner for federated queries. >> > AFAIK, >> > > there's no such thing on ARQ, and couldn't find any third-party libs >> for >> > > that. >> > > >> > > So my questions are: >> > > >> > > 1) do you know of any open source projects out there that deals with >> it? >> > > I'm willing to contribute. >> > > >> > > 2) If there is no such project, is a Transformer the right place to go >> > for >> > > it? I thought about extending TransformerCopy to reorder OpJoins to >> solve >> > > first those with smaller costs. >> > > >> > > Thanks! >> > > >> > > >> > > -- >> > > diogo patrão >> > > >> > >> > >> > >> > -- >> > I like: Like Like - The likeliest place on the web< >> > http://like-like.xenei.com> >> > Identity: https://www.identify.nu/[email protected] >> > LinkedIn: http://www.linkedin.com/in/claudewarren >> > >> > > > > -- > I like: Like Like - The likeliest place on the web<http://like-like.xenei.com> > Identity: https://www.identify.nu/[email protected] > LinkedIn: http://www.linkedin.com/in/claudewarren > -- I like: Like Like - The likeliest place on the web<http://like-like.xenei.com> Identity: https://www.identify.nu/[email protected] LinkedIn: http://www.linkedin.com/in/claudewarren
