Say you want to search for “run*”. That should match “run”, “runner”, “running”, “runs” etc. one term->many == multiterm expansion. Conceptually, the search becomes (run OR runner OR running OR runs), all terms actually found in the index that have the prefix “run”.
My advice would be to ignore it completely, that’s an expert level option that came about because we got really tired of explaining that wildcards didn’t used to have _any_ analysis done, so searching for “Run*" would not match “run” due to the case difference. Best, Erick > On Nov 6, 2019, at 7:21 AM, Alexandre Rafalovitch <[email protected]> wrote: > > It mentions it in the start paragraph "Prefix, Wildcard, Regex, etc." > > So, if you search for "abc*" it expands to all terms that start from > "abc", but then not everything can handle this situation as it is a > lot of terms in the same position. So, not all analyzers can handle > that and normally it is just an automatically built subset of safe > ones. > > I mark them with "(multi)" in my - very out of date, but still useful > - resource: http://www.solr-start.com/info/analyzers/ > > Regards, > Alex. > > On Wed, 6 Nov 2019 at 21:19, Paras Lehana <[email protected]> wrote: >> >> Hi Community, >> >> In Ref Guide 8.3's Understanding Analyzers subsection *Analysis for >> Multi-Term Expansion* >> <https://lucene.apache.org/solr/guide/8_3/analyzers.html#analysis-for-multi-term-expansion>, >> the text talks about multi-term expansion and explicit use of *analyzer >> type="multiterm"*. >> >> I could not understand what exactly is multi-term expansion and what are >> the use cases for using "multiterm". *[Q1]* >> >> -- >> -- >> Regards, >> >> *Paras Lehana* [65871] >> Development Engineer, Auto-Suggest, >> IndiaMART Intermesh Ltd. >> >> 8th Floor, Tower A, Advant-Navis Business Park, Sector 142, >> Noida, UP, IN - 201303 >> >> Mob.: +91-9560911996 >> Work: 01203916600 | Extn: *8173* >> >> -- >> IMPORTANT: >> NEVER share your IndiaMART OTP/ Password with anyone.
