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Query Pointers |
A keyword is simply one item or question for which you want information. A keyword is generally a noun but may also be a verb or some other part of speech. WAIS searches the database for documents that have words that match the keyword(s) that you've entered. Note that common words such as the conjunctions ("and", "but", etc.), pronouns ("I", "you", etc.), and prepositions ("of", "for", "into", etc) are ignored in by the search because they are too common across all documents.
When entering keywords, you may enter as many keywords as you like. Multiple keywords are treated as having an implicit boolean 'or' operator. For example, if you entered the keywords
women science
the server would return documents that contain the word "women" or the word "science". However, the server would rank documents that contain both words higher than documents that contain only one of the words.
Our WAIS server also supports boolean operators and nested queries. You can use the 'and' or 'not' operators to further refine queries. For example, if you entered the keywords
women and science not medicine
the server would only return documents that contain both the words "women" and "science" but that do not contain the word "medicine". If you wish to further refine your query, you can use nested queries of the form:
A and (((B or C) not (D and E and F)) or G).
It is also possible to specify partial keywords and literal phrase keywords.
The * symbol applied at the end of a partial keyword will match all documents that contain words that start with the partial word. For example, if you entered the keyword
hum*
the server would return documents that contain the words "hum", "hummingbird", "human", "humbug", etc.
If quotes (') or double quotes (") are used around the keywords, the server will return documents that contatin that phrase exactly. For example, if you entered the keywords
'women in science'
the server would only return documents that contain the full string "women in science". Note, the first part of a literal must be a word that is otherwise indexed. In other words, the literal cannot start with a symbol or other word delimiter. Also, within quotes, the boolean operators and the partial word * are not active. However, these features can be mixed in a query. For example, you can specify a query of the form:
'women in science' and bio* not medicine
In general, you should usually start out with a fairly simple query and refine it based on the results. However, since the server returns the 40 top ranking documents, if the documents you get back are not what you are looking for, you may need to refine your query.
