[SOLR-10832] Using "indexed" PointField for _version_ breaks VersionInfo.getMaxVersionFromIndex

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 6.7, 7.0
• Labels: numeric-tries-to-points
• Assignee: Chris M. Hostetter
• Reporter: Chris M. Hostetter
• Created: 06/Jun/17 23:36
• Updated: 08/Jun/19 15:20
• Resolved: 15/Jun/17 23:10

Description

If someone configures _version_ using a LongPointField which is indexed="true" then VersionInfo.getMaxVersionFromIndex() will incorrectly assume...

    // if indexed, then we have terms to get the max from
    if (versionField.indexed()) {
      LeafReader leafReader = SlowCompositeReaderWrapper.wrap(searcher.getIndexReader());
      Terms versionTerms = leafReader.terms(versionFieldName);
      Long max = (versionTerms != null) ? LegacyNumericUtils.getMaxLong(versionTerms) : null;

...which will not work because Point based fields have no Terms.

potential work around: configuring _version_ to use indexed="false" docValues="true" should cause this branch to be skipped and the existing ValueSource/DocValues based fallback to be used.

We should either:

• figure out if an alternative option exists for determining the "max" value of a LongPointField, and if so use that if versionField.indexed() && versionField.getType().isPointField()
• change VersionInfo.getAndCheckVersionField() to check if the version field IsPointField() and if so error unless indexed="false" && docValues="true"

Issue Links

• is related to: SOLR-10872 _version_ returns exception when changed to point field
• relates to: SOLR-10807 Randomize PointFields in all tests unless explicit reason not to