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This website uses the Verity search engine. This product provides a large number of options which enables the use of expert search techniques. You can build two types of query expressions: "simple" and "explicit." A simple query expression is typically a word or words. An explicit query expression can employ a number of operators and modifiers to refine the search. We provide a link to the publisher's documentation for those who may wish to create explicit queries. The following paragraphs describe the "simple" searches.
Search terms can be single words, phrases, lists of words separated by commas and words with wildcard characters. Simple queries search for whole words, so a search for sea will find only those results containing the word sea and not other words such as search. However wildcards are available, so you can search for sea* and retrieve results containing search as well.
Nonetheless, simple queries do exhibit stemming properties. That is, a search for sea will find words derived from the word sea such as seas (as opposed to search, which contains the string sea but is not derived from the word sea).
By providing a list of words separated by commas, the comma is taken to imply logical OR. That is, a search for sea, ocean will find all results with either the word sea or the word ocean or both. Without commas, a series of words is treated as a phrase, so searching for sea ocean will find all results with the exact phrase sea ocean in them.
In addition, simple queries allow for the use of the basic Boolean operators AND, OR, and NOT in a query. For instance,
sea AND ocean
finds all results in a collection containing both sea and ocean, whereas
sea NOT ocean
finds all results containing sea but not ocean.
Order of precedence applies when using Boolean operators; AND operators take precedence over OR operators. Therefore, in the expression
sea OR ocean AND lake
the expression ocean AND lake is evaluated first, and the result is then paired with sea to be evaluated in the remaining expression.
Using parentheses can override the order of precedence so that (sea OR ocean) AND lake
causes sea OR ocean to be evaluated first.
Using Wildcards
The following wildcard operators may be used in queries:
? Matches any single alphanumeric character
* Matches zero or more alphanumeric characters
[ ] Matches one of the characters contained between the brackets
{ } Matches all the patterns, separated by commas, contained in the curly brackets
^ When used inside square brackets, indicates that a match should be made for any character not contained in the brackets
- When used inside square brackets, indicates a range of characters
For example, consider the following patterns and their matches, outlined in the following table:
Pattern |
Match |
sea? |
Matches seas and seat but not sea |
sea* |
Matches seas and seat but also sea, search, seam, and any other combination starting with sea |
sea[st] |
Matches seas and seat but not seam, sea, or search |
sea {m, rch} |
Matches seam and search but not seat, seas or sea |
sea[^st] |
Matches seam and seal but not seas or seat |
sea[a-z] |
Matches every possible combination of sea followed by a single letter including seas, seat, seam, and seal |
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