Boolean operators enable you to construct complex logical expressions that include many different search words or phrases, including both inclusive and exclusive conditions. Ontolica supports the following standard Boolean operators:
When two search words (or clauses) are connected by an AND operator, then the expression will be true only for documents that include both terms (or when both clauses return true). When no operator is supplied, this is the default.
When two search words (or clauses) are connected by an OR operator, then the expression will be true for documents that include either one or both terms (or when one or both of the clauses return true).
When a search word (or clause) is proceeded by a NOT operator, then the expression will be true only for documents that do not include that word (or for which the clause returns false). You can also use a minus sign for this (-).
When two search words are separated by a NEAR operator, then the search will return only documents that contain those two words close to each other, but not pages that contain just one of the words, or even both words if they are far from each other (with several other words in between).