[ https://issues.apache.org/jira/browse/SOLR-7707?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Dennis Gove updated SOLR-7707: ------------------------------ Attachment: SOLR-7707.patch New correctly based patch attached. > Add StreamExpression Support to RollupStream > -------------------------------------------- > > Key: SOLR-7707 > URL: https://issues.apache.org/jira/browse/SOLR-7707 > Project: Solr > Issue Type: Improvement > Components: SolrJ > Reporter: Dennis Gove > Priority: Minor > Attachments: SOLR-7707.patch, SOLR-7707.patch, SOLR-7707.patch > > > This ticket is to add Stream Expression support to the RollupStream as > discussed in SOLR-7560. > Proposed expression syntax for the RollupStream (copied from that ticket) > {code} > rollup( > someStream(....), > over="fieldA, fieldB, fieldC", > min(fieldA), > max(fieldA), > min(fieldB), > mean(fieldD), > sum(fieldC) > ) > {code} > This requires making the *Metric types Expressible but I think that ends up > as a good thing. Would make it real easy to support other options on metrics > like excluding outliers, for example find the sum of values within 3 standard > deviations from the mean could be > {code} > sum(fieldC, limit=standardDev(3)) > {code} > (note, how that particular calculation could be implemented is left as an > exercise for the reader, I'm just using it as an example of adding additional > options on a relatively simple metric). > Another option example is what to do with null values. For example, in some > cases a null should not impact a mean but in others it should. You could > express those as > {code} > mean(fieldA, replace(null, 0)) // replace null values with 0 thus leading to > an impact on the mean > mean(fieldA, includeNull="true") // nulls are counted in the denominator but > nothing added to numerator > mean(fieldA, includeNull="false") // nulls neither counted in denominator nor > added to numerator > mean(fieldA, replace(null, fieldB), includeNull="true") // if fieldA is null > replace it with fieldB, include null fieldB in mean > {code} > so on and so forth. -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@lucene.apache.org For additional commands, e-mail: dev-h...@lucene.apache.org