lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Ryan Ernst (JIRA)" <j...@apache.org>
Subject [jira] [Updated] (LUCENE-7147) Improve disjoint check for geo distance query traversal
Date Tue, 29 Mar 2016 15:55:25 GMT

     [ https://issues.apache.org/jira/browse/LUCENE-7147?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Ryan Ernst updated LUCENE-7147:
-------------------------------
    Attachment: example-intersects-bbox-not-circle.html
                example-crosses-axis-not-center.html

I've attached 2 examples.They both use the same geo distance query. Imagine someone from London
says "I want to find places to travel within 1143km". So they do a distance search. The "intersects
bbox not circle" example shows how this would require us to compute the distances from london
to all the points indexes in the box covering Italy. The second example shows how if we were
to use the naive approach of using the latitude of the circle center, we would incorrectly
exclude a chunk of Poland thinking it did not intersect the circle because all corners are
outside the circle, and it lies completely above the circle center latitude, but in fact it
crosses the axis of the bbox.

> Improve disjoint check for geo distance query traversal
> -------------------------------------------------------
>
>                 Key: LUCENE-7147
>                 URL: https://issues.apache.org/jira/browse/LUCENE-7147
>             Project: Lucene - Core
>          Issue Type: Improvement
>            Reporter: Ryan Ernst
>         Attachments: LUCENE-7147.patch, example-crosses-axis-not-center.html, example-intersects-bbox-not-circle.html
>
>
> When doing geo distance queries, it is important to avoid traversing subtrees which do
not contain any relevant points. We currently have checks which compare the bbox of the query
to the bounds of the subtree. However, it is possible for a subtree to overlap the bbox, but
still not intersect the query. This issue is to improve that check to avoid unnecessary traversals.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: dev-help@lucene.apache.org


Mime
View raw message