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ASF subversion and git services commented on SOLR-14481: -------------------------------------------------------- Commit d883cd69fc2884352e0a363b98e3d5a37142dd52 in lucene-solr's branch refs/heads/jira/SOLR-14354 from Noble Paul [ https://gitbox.apache.org/repos/asf?p=lucene-solr.git;h=d883cd6 ] SOLR-14481: use classloader to open resource > Add drill Streaming Expression for efficient and accurate high cardinality > aggregation > -------------------------------------------------------------------------------------- > > 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 > Fix For: 8.6 > > 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: issues-unsubscr...@lucene.apache.org For additional commands, e-mail: issues-h...@lucene.apache.org