Search Issues in Dspace 6.4 while using "Contains" Operator on Title Control Keys

[Braxton Van Gundy]

Hello,

I have been chasing an odd behavior with the Dspace advance search.  We have a couple thousand documents with title control keys that are formatted like so "EXP22****", i.e. an actual title control key would be EXP227009.  

When I perform an advance search on the title control keys using the "contains" operator with just letters, i.e. title control key CONTAINS "EXP", the search results come back as expected, displaying all the documents with title control keys that contain "EXP".  However, if I perform the same search with letters AND numbers, i.e. "EXP22", nothing gets returned even though there are just as many documents that contain "EXP22" as there are that contain "EXP".  

I'm not seeing any errors  in the SOLR or Dspace logs, though oddly the query on the backend is slightly different for the "EXP" versus the "EXP22" search, I am not sure why it does this since I am not changing any of the params on my end besides the search string (see below).

Backend query for "EXP" search (from the SOLR log):

2022-12-05 15:57:12,139 INFO  org.apache.solr.core.SolrCore @ [search] webapp=/solr path=/select params={facet.field=author_filter&facet.field=subject_filter&f.author_filter.facet.offset=0&fl=handle,search.resourcetype,search.resourceid&start=0&fq=NOT(withdrawn:true)&fq=NOT(discoverable:false)&fq=titleControlKey:"EXP"&sort=score+desc&f.author_filter.facet.sort=count&rows=10&f.subject_filter.facet.limit=12&version=2&facet.query=dateIssued.year:[2000+TO+2006]&facet.query=dateIssued.year:[1990+TO+1999]&facet.query=dateIssued.year:[1980+TO+1989]&facet.query=dateIssued.year:[1970+TO+1979]&facet.query=dateIssued.year:[1960+TO+1969]&facet.query=dateIssued.year:[1950+TO+1959]&facet.query=dateIssued.year:[1940+TO+1949]&facet.query=dateIssued.year:[1930+TO+1939]&facet.query=dateIssued.year:[1924+TO+1929]&q=*:*&spellcheck.q=*:*&spellcheck=true&f.subject_filter.facet.sort=count&facet.mincount=1&facet=true&wt=javabin&facet.offset=0&spellcheck.collate=true&f.author_filter.facet.limit=12&f.subject_filter.facet.offset=0} hits=20551 status=0 QTime=7

Backend query for "EXP22" search

2022-12-05 15:57:38,785 INFO  org.apache.solr.core.SolrCore @ [search] webapp=/solr path=/select params={facet.field=author_filter&facet.field=subject_filter&f.author_filter.facet.offset=0&fl=handle,search.resourcetype,search.resourceid&start=0&fq=NOT(withdrawn:true)&fq=NOT(discoverable:false)&fq=titleControlKey:"EXP22"&sort=score+desc&f.author_filter.facet.sort=count&rows=10&f.subject_filter.facet.limit=12&version=2&q=*:*&spellcheck.q=*:*&spellcheck=true&f.subject_filter.facet.sort=count&facet.mincount=1&facet=true&wt=javabin&facet.offset=0&spellcheck.collate=true&f.author_filter.facet.limit=12&f.subject_filter.facet.offset=0} hits=0 status=0 QTime=0

Has anyone seen this before?

(I did try completely rebuilding the search index with no luck, it made no difference)

Thank you,

Braxton VanGundy