[ https://issues.apache.org/jira/browse/SOLR-9080?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
David Smiley updated SOLR-9080: ------------------------------- Affects Version/s: 6.0 Fix Version/s: (was: 6.0) 6.1 > DateMath is broken before the year 1582 > --------------------------------------- > > Key: SOLR-9080 > URL: https://issues.apache.org/jira/browse/SOLR-9080 > Project: Solr > Issue Type: Bug > Affects Versions: 6.0 > Reporter: David Smiley > Assignee: David Smiley > Fix For: 6.1 > > Attachments: SOLR_9080_DateMath_should_not_use_Calendar_API.patch > > > In Solr 6.0, dates are parsed using the Java 8 java.time API. It formerly > was parsed using java.util.SimpleDateFormat which uses > java.util.GregorianCalendar. I've learned that the java.time API does _not_ > switch to a different algorithm at the Gregorian Change Date (year 1582) > whereas GregorianCalendar does. A ramification of this is that the > milliseconds before epoch value is different between the APIs for dates prior > to this year. They both round-trip between themselves but not between each > other prior to this date. Thus, anyone indexing historical dates must > re-index when moving to Solr 6. > What was _not_ changed in the parsing code was Solr's date-math logic -- it > still uses the Calendar API. This works for dates after 1582 but before, > it'll introduce discrepancies. Here's an example showing weird behavior: > http://localhost:8983/solr/techproducts/select?facet.range.end=1400-01-01T00:00:00Z&facet.range.gap=%2B10YEARS&facet.range.start=1300-01-01T00:00:00Z/YEAR&facet.range=manufacturedate_dt&facet=on&indent=on&q=*:*&rows=0&wt=json > Note that the year 1300 rounded down to the year, becomes 1299 January 8th > (weird in and of itself) and that subsequent gaps start on the 9th. > {noformat} > "counts":[ > "1299-01-08T00:00:00Z",0, > "1309-01-09T00:00:00Z",0, > "1319-01-09T00:00:00Z",0, ... > {noformat} > This weirdness will show itself for units at the year or month level, but not > below that (from what I'm seeing). In other words, if facet.range.gap is at > this amount, or otherwise using the date math syntax to round or add a year > or month, there will be issues like this. Otherwise there doesn't seem to be > an issue. > I think the solution is clearly to switch the date math code to use the > java.time API. -- 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