On Fri, Jun 17, 2016 at 2:10 PM, Oleg Bartunov <obartu...@gmail.com> wrote:
> > > On Fri, Jun 17, 2016 at 9:32 AM, Andreas Joseph Krogh <andr...@visena.com> > wrote: > >> På torsdag 16. juni 2016 kl. 00:50:45, skrev Jeff Janes < >> jeff.ja...@gmail.com>: >> >> On Wed, Jun 15, 2016 at 3:56 AM, Andreas Joseph Krogh <andr...@visena.com >> > wrote: >>> >>> Hi. >>> >>> First; Is this the correct forum to ask questions about the Postgres >>> Pro's new RUM-index? >>> >>> If not, please point me to the right forum. >>> >> >> I think that https://github.com/postgrespro/rum/issues might be the best >> forum. >> >> >> Oleg and friends; Should we use GitHub-issues as forum (one issue per >> question/thread?), pgsql-general or something else? >> > > Andreas, > > we are hardly working on our internal version of rum and will open it > after resolving some issues. I think the best place to discuss it is > -hackers. > Ah, as someone corrected me, we are working hard ! > > > >> >> >> Note that GIN does almost what I want, except use the index when sorting >>> by "sent"-timestamp. >>> >>> So I wonder if RUM can do any better? >>> What I don't understand is how to have "folder_id" as part of the >>> RUM-index so that I can search in *an array* of folders using the >>> index, *AND* have the whole result sorted by "sent"-timestamp also >>> using the RUM-index. >>> >> >> I think you would have to implement an operator for integers for RUM much >> like btree_gin does for GIN. Sorry don't know how to do that, except to >> say look in the RUM code to see how it does it for time-stamps. >> >> >>> >>> In the (limited) documentation sorting using timestamp is done like this: >>> >>> ORDER BY sent <-> '2000-01-01'::TIMESTAMP >>> >>> which I don't understand; Why must one specify a value here, and how >>> does that value affect the result? >>> >> >> >> This is essentially identical to ORDER BY ABS(sent - >> '2000-01-01'::TIMESTAMP); except it can use the index. >> >> So maybe pick a constant outside the range of possible values, and use >> that as one argument to <->. >> >> >> This should be unnecessary and hidden from the user. Maybe some "ORDER BY >> rum_timestamp(sent)" or something could abstract away stuff to make it much >> clearer to the user? >> -- >> *Andreas Joseph Krogh* >> CTO / Partner - Visena AS >> Mobile: +47 909 56 963 >> andr...@visena.com >> www.visena.com >> <https://www.visena.com> >> >> > >
