Hi Joel,
Thanks for the reply!
I have indexed graph data in solr where an "event" can have one or more
"participants". Thus, it's a graph of "participants" connected to each
other via "events". Because participants are multiple, I am indexing the
graph as follows.
event------event_participant_child------participant
Now my end goal is this, I have a list of "events" and for that list I want
to plot a graph of "participants" by connecting them via events (which have
to be from the original list). I get this list of "events" from a search()
function which I use as my seed expression for gatherNodes().
I am doing a two hop graph traversal as follows.
having(
having(
gatherNodes(
collection1,
having(
gatherNodes(
collection1,
search(.....), // gets list of events with each
node having "eventId"
walk=eventId->eventId, // walk to event_participant_child
document which has both "eventId" and "participantId"
gather="participantId",
trackTraversal="true", scatter="leaves",
count(*)
),
gt(count(*),0)
),
walk=node->participantId,
gather="eventId",
fq=(),
// limit traversal to original list of events by
using search() here??
trackTraversal="true", scatter="branches",
count(*)
),
eq(level,0)
),
gt(count(*),1)
)
I am able to get the graph I want from ancestors fields of nodes which are
at level 0. Essentially, these are the events from my original list. Using
"having()" function, I am able to limit the response so that it only
includes original events. But it would be a great improvement if I can also
limit the traversal so that only events from original list are visited at
second hop. That is why, I want to apply original search() function as a
filter in outer gatherNodes() function. I know it's a long shot but
considering the potential improvement in performance, I was curious. Please
let me know if you feel there is a better approach.
Thanks
- Pratik
On Thu, Jun 21, 2018 at 7:05 PM, Joel Bernstein <joels...@gmail.com> wrote:
> Currently the gatherNodes expression can only be filtered by a traditional
> filter query. I'm curious about the type of expression you are thinking of
> filtering by?
>
> Joel Bernstein
> http://joelsolr.blogspot.com/
>
> On Wed, Jun 20, 2018 at 1:54 PM, Pratik Patel <pra...@semandex.net> wrote:
>
> > We can limit the scope of graph traversal by applying some filter along
> the
> > way as follows.
> >
> > gatherNodes(emails,
> > walk="john...@apache.org->from",
> > fq="body:(solr rocks)",
> > gather="to")
> >
> >
> > Is it possible to replace "body:(solr rocks)" by some streaming
> expression
> > like "search" function for example? Like as follows..
> >
> > gatherNodes(emails,
> > walk="john...@apache.org->from",
> > fq="search(...)", // use streaming expression as filter
> > gather="to")
> >
> >
> >
> > In my case, it would improve performance significantly if one can do
> that.
> > Other approach I can think of is to save results of "search" streaming
> > expression in some variable in pipeline and then use it at multiple
> places
> > including "fq" clause of "gatherNodes". Is it possible to do something
> like
> > this?
> >
>
