Perhaps not relevant in this case, but for the record there is one more SOLR behavior affected by multiValued:
3) when faceting, a multiValued field always uses the TermEnum algorithm rather than the FieldCache algorithm. depending on the data, this can have a dramatic effect on faceting performance: TermEnum is good for a limited number of different indexed terms in the field, and allows multiple terms per field per document, while FieldCache is good for a large number of indexed values relative to the number of documents, and only allows a single term per field per document. - J.J. At 10:57 AM -0700 3/16/07, Chris Hostetter wrote: >: I would be shocked if you noticed any performance difference between a >: single-valued field and a multivalued field with one entry. > >there shouldnt' be any difference at all in search performance, or index >size ... marking a field multiValued should only have two effects: > > 1) on document add/update no error will be thrown if more then one value >is enncountered > 2) the response writer may created a slightly larger response document >since it's rendering a list instead of an item (even if every document >returned only has one item in the list) > >(this is one of hte big differneces between using version=2.0 and >version=2.1 with XmlResponseWriter ... in 2.0 it would only make a list if >there is more then one item - even if the field is multiValued) > > > >-Hoss
