[
https://issues.apache.org/jira/browse/SOLR-1682?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12799180#action_12799180
]
Shalin Shekhar Mangar commented on SOLR-1682:
---------------------------------------------
bq. Shalin, I tried your patch out and I ran into a few problems with sorting
and the collapse counts which turned out to be bugs.
Thanks Martijn.
{quote}
Though I have a question about the response format. When collapse.threshold is
> 1 and more than one documents is collapsed then the collapse.count is named
group.size. The field group.numFound is then added as well. Why did you gave it
a different name?
{quote}
Actually I intended to rename "collapse.value" to "group.value" and
"collapse.count" to "group.numFound" but I forgot to do it in both the places.
* group.numFound = the total number of documents belonging to this group (i.e.
have the same group.value)
* group.size = the number of documents in this result set belonging to the same
group which is equal to min(group.numFound, collapse.threshold)
So when collapse.threshold = 1, group.size=1 and group.numFound will be equal
to the number of documents in the same group. Suppose collapse.threshold = 5,
but group.numFound=4 then group.size=4. The group.size is required to read all
docs belonging to the same group without having to maintain a set. Let me know
if you have suggestions for a better name than these.
{quote}
When collapse.threshold is larger than one two collectors are used. I
understand that in both situations a different algorithm is used. But now also
a search is done twice. Shouldn't it be better to have two complete distinct
collectors that don't depend on one another?
{quote}
We can have distinct collectors. The CollapsedDocCollector uses some of the
data that TopGroupCollector gathers and that is why it uses it directly. We
could keep references to the individual objects that are needed too. As I said,
this is just a PoC and not the final design.
I'll give a new patch with the names fixed for both the cases.
> Implement CollapseComponent
> ---------------------------
>
> Key: SOLR-1682
> URL: https://issues.apache.org/jira/browse/SOLR-1682
> Project: Solr
> Issue Type: Sub-task
> Components: search
> Reporter: Martijn van Groningen
> Assignee: Shalin Shekhar Mangar
> Fix For: 1.5
>
> Attachments: field-collapsing.patch, SOLR-1682.patch, SOLR-236.patch
>
>
> Child issue of SOLR-236. This issue is dedicated to field collapsing in
> general and all its code (CollapseComponent, DocumentCollapsers and
> CollapseCollectors). The main goal is the finalize the request parameters and
> response format.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
