[
https://issues.apache.org/jira/browse/SOLR-14481?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Joel Bernstein updated SOLR-14481:
----------------------------------
Attachment: SOLR-14481.patch
> Add drill Streaming Expression
> ------------------------------
>
> Key: SOLR-14481
> URL: https://issues.apache.org/jira/browse/SOLR-14481
> Project: Solr
> Issue Type: New Feature
> Components: streaming expressions
> Reporter: Joel Bernstein
> Assignee: Joel Bernstein
> Priority: Major
> Attachments: SOLR-14481.patch, SOLR-14481.patch
>
>
> This ticket will add the *drill* Streaming Expression. The drill Streaming
> Expression is a wrapper around the functionality that is described in
> SOLR-14470. The idea is for drill to contact the /export handler on one
> replica in each shard of a collection and pass four parameters:
> * q: query
> * fl: field list
> * sort: sort spec
> * expr: The Streaming Expression sent to the /export handler to be executed.
> The export handler will pass the result set through the streaming expression
> performing an aggregation on the sorted result set and return the aggregated
> tuples. The drill expression will simply maintain the sort order of the
> tuples and emit them so that a wrapper expression can perform operations on
> the sorted aggregate tuples.
> Sample syntax:
> {code:java}
> drill(collection1, q="*:*", fl="a,b,c", sort="a desc, b desc",
> rollup(input(), over="a,b", sum(c))) {code}
> In order to finish the aggregation other expressions can be used:
> {code:java}
> rollup(
> select(
> drill(collection1,
> q="*:*",
> fl="a,b,c",
> sort="a desc, b desc",
> rollup(input(), over="a,b", sum(c))),
> a,
> b,
> sum(c) as sums),
> over="a, b",
> sum(sums))
>
> {code}
> This provides fast aggregation over fields with infinite cardinality by
> pushing down the first level of aggregation into the /export handler.
>
>
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
