: 3) when faceting, a multiValued field always uses the TermEnum : algorithm rather than the FieldCache algorithm.
Damn. Good catch J.J. ... i totally forgot about that and it certainly is a "performance penalty" if you use facets. : 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. -Hoss
