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==Query Issues (SPARQL, SQL, etc.)==

==={{{bif:contains}}} and REGEX Searches Produce Different Results===

{{{bif:contains}}} looks for phrases or independent words, and it may normalize words that use non-canonical Unicode chars. It can also search in XML/HTML documents. In addition, even if one and the same query string is valid for both REGEX and {{{bif:contains}}}, then the meaning may differ. For REGEX, pattern "Paris Hilton" is precisely two words delimited by single whitespace byte. For {{{ bif:contains}}}, "Paris Hilton" means that the document should contain word "Paris" and word "Hilton",
in any places and in any order. See [[http://docs.openlinksw.com/virtuoso/queryingftcols.html]] for details of {{{bif:contains}}} query string syntax.