Solr statistics records created before DSpace 6.x are still indexed with their legacy id.
The following PR will migrate legacy statistics records to use DSpace 6x UUID values: https://github.com/DSpace/DSpace/pull/1774
Because this PR requires a SOLR schema change, we have deferred this fix until DSpace 7x.
DSpace 6.0 had some code in place that will search for either a UUID or a legacy id when displaying usage records. This logic was incomplete.
The following PR addresses that issue: https://github.com/DSpace/DSpace/pull/1782
Unfortunately, when statistics records are retrieved by facet query separate counts are returned for records indexed by legacyId and records indexed by UUID.
A fix for this bug would require changes to the following code. Much of this code is quite old and it appears to need significant refactoring.
I recommend that we create a new ticket to refactor this code in DSpace 7.x. Perhaps the changes for DS-3602 should be merged in the meantime.
